Immunoglobulins

ABSTRACT

The present invention relates to antigen binding proteins to human IL-13, including anti-IL-13 antibodies and anti-IL-3/anti-IL-4 mAbdAbs, pharmaceutical formulations containing them and to the use of such antigen binding proteins in the treatment and/or prophylaxis of inflammatory diseases such as asthma or IPF.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. Provisional Application Nos. 61/181,833 and 61/288,930, filed on May 28, 2009 and Dec. 22, 2009, respectively. These applications are incorporated by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates to antigen binding proteins, particularly antibodies that bind to interleukin 13 (IL-13) and neutralise the activity thereof, polynucleotides encoding such antigen binding proteins, pharmaceutical formulations containing said antigen binding proteins and to the use of such antigen binding proteins in the treatment and/or prophylaxis of diseases associated with inflammation, such as asthma. Other aspects, objects and advantages of the present invention will become apparent from the description below.

BACKGROUND OF THE INVENTION Interleukin-13 (IL-13)

IL-13 is a 12 kDa secreted cytokine originally described as a T cell-derived cytokine that inhibits inflammatory cytokine production. Structural studies indicate that it has a four-helical bundle arrangement held by two disulphide bonds. Although IL-13 has four potential glycosylation sites, analysis of native IL-13 from rat lung has indicated that it is produced as an unglycosylated molecule. Expression of human IL-13 from NSO and COS-7 cells confirms this observation (Eisenmesser et al, J. Mol. Biol. 2001 310(1):231-241; Moy et al, J. Mol. Biol. 2001 310(1):219-230; Cannon-Carlson et al, Protein Expression and Purification 1998 12(2):239-248).

IL-13 has been implicated in asthma, Chronic Obstructive Pulmonary Disease (COPD), Allergic disease including atopic dermatitis and allergic rhinitis, Esophagal eosinophilia, Oncology Indications, e.g. B-cell chronic lymphocytic leukemia (B-CLL) and Hodgkin's disease, Inflammatory Bowel Diseases e.g. ulcerative colitis, Crohn's disease and indeterminate colitis, Psoriasis and Psoriatic Arthritis, Acute graft-versus-host disease, Diabetic nephropathy, Fibrotic Conditions such as Pulmonary fibrosis e.g. Idiopathic Pulmonary Fibrosis (IPF).

SUMMARY OF INVENTION

The invention provides antigen binding proteins which bind to IL-13, for example IL-13 antibodies, and to the combination of such IL-13 antibodies with an IL-4 antagonist and/or an IL-5 antagonist. The IL-13 antibodies of the present invention are related to, or derived from, a murine mAb 6A1, wherein the CDRH3 is mutated. The 6A1 murine heavy chain variable region amino acid sequence is provided as SEQ ID NO: 58. The 6A1 murine light chain variable region amino acid sequence is provided as SEQ ID NO 59.

The heavy chain variable regions (VH) of the present invention comprise the following CDRs (as defined by Kabat (Kabat et al; Sequences of proteins of Immunological Interest NIH, 1987)):

The CDRs of the heavy chain variable regions of the present invention may comprise the following CDRs:

CDR According to Kabat H1 DTYMH (SEQ ID NO: 1) H2 TIDPANGNTKYVPKFQG (SEQ ID NO: 2) H3 WIYDDYHYDDYYAMDY (SEQ ID NO: 4); or SVYDDYHYDDYYAMDY (SEQ ID NO: 5); or SIFDDYHYDDYYAMDY (SEQ ID NO: 6); or SIYEDYHYDDYYAMDY (SEQ ID NO: 7); or SIYDDYAYDDYYAMDY (SEQ ID NO: 8); or SIYDDYEYDDYYAMDY (SEQ ID NO: 9); or SIYDDYQYDDYYAMDY (SEQ ID NO: 10); or SIYDDYRYDDYYAMDY (SEQ ID NO: 11); or SIYDDYSYDDYYAMDY (SEQ ID NO: 12); or SIYDDYTYDDYYAMDY (SEQ ID NO: 13) or SIYDDYVYDDYYAMDY (SEQ ID NO: 14); or SIYDDYHADDYYAMDY (SEQ ID NO: 15); or SIYDDYHIDDYYAMDY (SEQ ID NO: 16); or SIYDDYHWDDYYAMDY (SEQ ID NO: 17); or SIYDDYHVDDYYAMDY (SEQ ID NO: 18)

The light chain variable regions of the present invention comprise the following CDRs (as defined by Kabat):

CDR According to Kabat L1 RSSQNIVHINGNTYLE (SEQ ID NO: 19) L2 KISDRFS (SEQ ID NO: 20) L3 FQGSHVPWT (SEQ ID NO: 21)

The CDR sequences of antibodies can be determined by the Kabat numbering system (Kabat et al; Sequences of proteins of Immunological Interest NIH, 1987), as set out in the tables above, alternatively they can be determined using the Chothia numbering system (Al-Lazikani et al., (1997) JMB 273, 927-948), the contact definition method (MacCallum R. M., and Martin A. C. R. and Thornton J. M, (1996), Journal of Molecular Biology, 262 (5), 732-745) or any other established method for numbering the residues in an antibody and determining CDRs known to the skilled man in the art.

The CDRs of the invention described herein may be defined by any of these methods, or by using a combination of Chothia and Kabat numbering, for example CDRH1 may be defined as comprising FYIKDTYMH (SEQ ID NO 60) or GFYIKDTYMH (SEQ ID NO 61).

The present invention also provides an antigen-binding protein comprising the IL-13 antibody of the present invention which is linked to one or more epitope-binding domains, for example an antigen-binding protein comprising the IL-13 antibody of the present invention linked to an epitope-binding domain which is capable of binding to IL-4, or an antigen-binding protein comprising the IL-13 antibody of the present invention linked to an epitope-binding domain which is capable of binding to IL-5, or an antigen-binding protein comprising the IL-13 antibody of the present invention linked to a first epitope-binding domain which is capable of binding to IL-4 and a second epitope-binding domain which is capable of binding to IL-5.

The present invention also provides a method of decreasing the aggregation propensity of an immunoglobulin single variable domain, for example a human VK domain antibody, by mutation of residue 89 (kabat numbering) to ‘Q’ (glutamine). In one embodiment this method can be applied to the anti-IL-4 domain antibody of SEQ ID NO: 80, resulting in a mutated dAb sequence, for example SEQ ID NO:94.

Such mutated dAbs may be alone or as part of a larger sequence, for example part of a mAbdAb sequence, resulting in for example, a dAb comprising a sequence selected from SEQ ID NO: 117-134.

The invention also provides human VK dAbs which have improved aggregation profiles, for example a human VK dAb derived from a germline framework selected from IGKV1-17, IGKV1D-17, IGKV1/OR2-108, IGKV1-6, IGKV5-2, IGKV1D-42, IGKV2-24, IGKV2-28, IGKV2-30, IGKV2-40, IGKV2D-29, IGKV2D-30, IGKV2D-24 and IGKV6-21 wherein residue 89 (kabat numbering) of the VK dAb is ‘Q’ (glutamine). In one such embodiment the VK dAb comprises germline framework regions selected from the germline frameworks of IGKV1-17, IGKV1D-17, IGKV1/OR2-108, IGKV1-6, IGKV5-2, IGKV1D-42, IGKV2-24, IGKV2-28, IGKV2-30, IGKV2-40, IGKV2D-29, IGKV2D-30, IGKV2D-24 and IGKV6-21 wherein residue 89 (kabat numbering) of the VK dAb is ‘Q’ (glutamine).

In one embodiment the invention provides a human dAb comprising the sequence of SEQ ID NO: 94.

The invention also provides a polynucleotide sequence encoding a heavy chain of any of the antigen-binding proteins described herein, and a polynucleotide encoding a light chain of any of the antigen-binding proteins described herein. Such polynucleotides represent the coding sequence which corresponds to the equivalent polypeptide sequences, however it will be understood that such polynucleotide sequences could be cloned into an expression vector along with a start codon, an appropriate signal sequence and a stop codon.

The invention also provides a recombinant transformed or transfected host cell comprising one or more polynucleotides encoding a heavy chain and a light chain of any of the antigen-binding proteins described herein.

The invention further provides a method for the production of any of the antigen-binding proteins described herein which method comprises the step of culturing a host cell comprising a first and second vector, said first vector comprising a polynucleotide encoding a heavy chain of any of the antigen-binding proteins described herein and said second vector comprising a polynucleotide encoding a light chain of any of the antigen-binding proteins described herein, in a suitable culture media, for example serum-free culture media.

The invention further provides a pharmaceutical composition comprising an antigen-binding protein as described herein a pharmaceutically acceptable carrier.

In a further aspect, the present invention provides a method of treatment or prophylaxis of diseases or disorders associated with atopic diseases/disorders and chronic inflammatory diseases/disorders by administration of the antigen binding protein of the present invention. Of particular interest is their use in the treatment of asthma, such as allergic asthma, particularly severe asthma (that is asthma that is unresponsive to current treatment, including systemically administered corticosteroids; see Busse W W et al, J. Allergy Clin. Immunol 2000, 106: 1033-1042), “difficult” asthma (defined as the asthmatic phenotype characterised by failure to achieve control despite maximally recommended doses of prescribed inhaled steroids, see Barnes P J (1998), Eur Respir J 12:1208-1218), “brittle” asthma (defines a subgroup of patients with severe, unstable asthma who maintain a wide peak expiratory flow (PEF) variability despite high doses of inhaled steroids, see Ayres J G et al (1998) Thorax 58:315-321), nocturnal asthma, premenstrual asthma, steroid resistant asthma (see Woodcock A J (1993) Eur Respir J 6:743-747), steroid dependent asthma (defined as asthma that can be controlled only with high doses of oral steroids), aspirin induced asthma, adult-onset asthma, paediatric asthma. Antibodies of the invention may be used to prevent, reduce the frequency of, or mitigate the effects of acute, asthmatic episodes (status asthmaticus). Antibodies of the invention may also be used to reduce the dosing required (either in terms of amount administered or frequency of dosing) of other medicaments used in the treatment of asthma. For example, antibodies of the invention may be used to reduce the dosing required for steroid treatment of asthma such as corticosteroid treatment (“steroid sparing”). Other diseases or disorders that may be treated with antibodies of the invention include atopic dermatitis, allergic rhinitis, Crohn's disease, chronic obstructive pulmonary disease (COPD), eosinophilic esophagitis, fibrotic diseases or disorders such as idiopathic pulmonary fibrosis, progressive systemic sclerosis (scleroderma), hepatic fibrosis, hepatic granulomas, schistosomiasis, leishmaniasis, and diseases of cell cycle regulation, e.g. Hodgkins disease, B cell chronic lymphocytic leukaemia.

In another aspect, the invention provides the use of an antigen binding protein of the invention in the preparation of a medicament for treatment or prophylaxis of atopic diseases/disorders and chronic inflammatory diseases/disorders. Of particular interest is their use in the treatment of asthma, such as allergic asthma, particularly severe asthma (that is asthma that is unresponsive to current treatment, including systemically administered corticosteroids; see Busse W W et al, J. Allergy Clin. Immunol 2000, 106: 1033-1042), “difficult” asthma (defined as the asthmatic phenotype characterised by failure to achieve control despite maximally recommended doses of prescribed inhaled steroids, see Barnes P J (1998), Eur Respir J 12:1208-1218), “brittle” asthma (defines a subgroup of patients with severe, unstable asthma who maintain a wide peak expiratory flow (PEF) variability despite high doses of inhaled steroids, see Ayres J G et al (1998) Thorax 58:315-321), nocturnal asthma, premenstrual asthma, steroid resistant asthma (see Woodcock A J (1993) Eur Respir J 6:743-747), steroid dependent asthma (defined as asthma that can be controlled only with high doses of oral steroids), aspirin induced asthma, adult-onset asthma, paediatric asthma. Antibodies of the invention may be used to prevent, reduce the frequency of, or mitigate the effects of acute, asthmatic episodes (status asthmaticus). Antibodies of the invention may also be used to reduce the dosing required (either in terms of amount administered or frequency of dosing) of other medicaments used in the treatment of asthma. For example, antibodies of the invention may be used to reduce the dosing required for steroid treatment of asthma such as corticosteroid treatment (“steroid sparing”). Other diseases or disorders that may be treated with antibodies of the invention include atopic dermatitis, allergic rhinitis, Crohn's disease, chronic obstructive pulmonary disease (COPD), eosinophilic esophagitis, fibrotic diseases or disorders such as idiopathic pulmonary fibrosis, progressive systemic sclerosis (scleroderma), hepatic fibrosis, hepatic granulomas, schistosomiasis, leishmaniasis, and diseases of cell cycle regulation, e.g. Hodgkins disease, B cell chronic lymphocytic leukaemia.

Other aspects and advantages of the present invention are described further in the detailed description and the embodiments thereof.

DEFINITIONS

The term “binds to human IL-13” as used throughout the present specification in relation to antigen binding proteins thereof of the invention means that the antigen binding protein binds human IL-13 (hereinafter referred to as hIL-13) with no or insignificant binding to other human proteins such as IL-4. In particular the antigen binding proteins of the present invention bind to human IL-13 in that they can be seen to bind to human IL-13 in a Biacore assay (for example the Biacore assay described in example 3). The term however does not exclude the fact that certain antigen binding proteins of the invention may also be cross-reactive with IL-13 from other species, for example cynomolgus IL-13.

The term “antigen binding protein” as used herein refers to antibodies, antibody fragments and other protein constructs which are capable of binding to and neutralising human IL-13.

The terms Fv, Fc, Fd, Fab, or F(ab)₂ are used with their standard meanings (see, e.g., Harlow et al., Antibodies A Laboratory Manual, Cold Spring Harbor Laboratory, (1988)).

A “chimeric antibody” refers to a type of engineered antibody which contains a naturally-occurring variable region (light chain and heavy chains) derived from a donor antibody in association with light and heavy chain constant regions derived from an acceptor antibody.

A “humanised antibody” refers to a type of engineered antibody having its CDRs derived from a non-human donor immunoglobulin, the remaining immunoglobulin-derived parts of the molecule being derived from one (or more) human immunoglobulin(s). In addition, framework support residues may be altered to preserve binding affinity (see, e.g., Queen et al., Proc. Natl. Acad Sci USA, 86:10029-10032 (1989), Hodgson et al., Bio/Technology, 9:421 (1991)). A suitable human acceptor antibody may be one selected from a conventional database, e.g., the KABAT® database, Los Alamos database, and Swiss Protein database, by homology to the nucleotide and amino acid sequences of the donor antibody. A human antibody characterized by a homology to the framework regions of the donor antibody (on an amino acid basis) may be suitable to provide a heavy chain constant region and/or a heavy chain variable framework region for insertion of the donor CDRs. A suitable acceptor antibody capable of donating light chain constant or variable framework regions may be selected in a similar manner. It should be noted that the acceptor antibody heavy and light chains are not required to originate from the same acceptor antibody. The prior art describes several ways of producing such humanised antibodies—see for example EP-A-0239400 and EP-A-054951

The term “donor antibody” refers to an antibody (monoclonal, and/or recombinant) which contributes the amino acid sequences of its variable regions, CDRs, or other functional fragments or analogs thereof to a first immunoglobulin partner, so as to provide the altered immunoglobulin coding region and resulting expressed altered antibody with the antigenic specificity and neutralizing activity characteristic of the donor antibody.

The term “acceptor antibody” refers to an antibody (monoclonal and/or recombinant) heterologous to the donor antibody, which contributes all (or any portion, but in some embodiments all) of the amino acid sequences encoding its heavy and/or light chain framework regions and/or its heavy and/or light chain constant regions to the first immunoglobulin partner. In certain embodiments a human antibody is the acceptor antibody.

“CDRs” are defined as the complementarity determining region amino acid sequences of an antibody which are the hypervariable regions of immunoglobulin heavy and light chains. See, e.g., Kabat et al., Sequences of Proteins of Immunological Interest, 4th Ed., U.S. Department of Health and Human Services, National Institutes of Health (1987). There are three heavy chain and three light chain CDRs (or CDR regions) in the variable portion of an immunoglobulin. Thus, “CDRs” as used herein refers to all three heavy chain CDRs, or all three light chain CDRs (or both all heavy and all light chain CDRs, if appropriate). The structure and protein folding of the antibody may mean that other residues are considered part of the antigen binding region and would be understood to be so by a skilled person. See for example Chothia et al., (1989) Conformations of immunoglobulin hypervariable regions; Nature 342, p 877-883.

As used herein the term “domain” refers to a folded protein structure which has tertiary structure independent of the rest of the protein. Generally, domains are responsible for discrete functional properties of proteins and in many cases may be added, removed or transferred to other proteins without loss of function of the remainder of the protein and/or of the domain. An “antibody single variable domain” is a folded polypeptide domain comprising sequences characteristic of antibody variable domains. It therefore includes complete antibody variable domains and modified variable domains, for example, in which one or more loops have been replaced by sequences which are not characteristic of antibody variable domains, or antibody variable domains which have been truncated or comprise N- or C-terminal extensions, as well as folded fragments of variable domains which retain at least the binding activity and specificity of the full-length domain.

The phrase “immunoglobulin single variable domain” refers to an antibody variable domain (V_(H), V_(HH), V_(L)) that specifically binds an antigen or epitope independently of a different V region or domain. An immunoglobulin single variable domain can be present in a format (e.g., homo- or hetero-multimer) with other, different variable regions or variable domains where the other regions or domains are not required for antigen binding by the single immunoglobulin variable domain (i.e., where the immunoglobulin single variable domain binds antigen independently of the additional variable domains). A “domain antibody” or “dAb” is the same as an “immunoglobulin single variable domain” which is capable of binding to an antigen as the term is used herein. An immunoglobulin single variable domain may be a human antibody variable domain, but also includes single antibody variable domains from other species such as rodent (for example, as disclosed in WO 00/29004), nurse shark and Camelid V_(HH) dAbs (nanobodies). Camelid V_(HH) are immunoglobulin single variable domain polypeptides that are derived from species including camel, llama, alpaca, dromedary, and guanaco, which produce heavy chain antibodies naturally devoid of light chains. Such V_(HH) domains may be humanised according to standard techniques available in the art, and such domains are still considered to be “domain antibodies” according to the invention. As used herein “V_(H) includes camelid V_(HH) domains. NARV are another type of immunoglobulin single variable domain which were identified in cartilaginous fish including the nurse shark. These domains are also known as Novel Antigen Receptor variable region (commonly abbreviated to V(NAR) or NARV). For further details see Mol. Immunol. 44, 656-665 (2006) and US20050043519A.

The term “Epitope-binding domain” refers to a domain that specifically binds an antigen or epitope independently of a different V region or domain, this may be a domain antibody (dAb), for example a human, camelid or shark immunoglobulin single variable domain or it may be a domain which is a derivative of a non-Immunoglobulin scaffold, for example a non-immunoglobulin scaffold selected from the group consisting of CTLA-4 (Evibody); lipocalin; Protein A derived molecules such as Z-domain of Protein A (Affibody, SpA), A-domain (Avimer/Maxibody); Heat shock proteins such as GroEI and GroES; transferrin (trans-body); ankyrin repeat protein (DARPin); peptide aptamer; C-type lectin domain (Tetranectin); human γ-crystallin and human ubiquitin (affilins); PDZ domains; scorpion toxinkunitz type domains of human protease inhibitors; and fibronectin (adnectin); which has been subjected to protein engineering in order to obtain binding to a ligand other than the natural ligand.

CTLA-4 (Cytotoxic T Lymphocyte-associated Antigen 4) is a CD28-family receptor expressed on mainly CD4+ T-cells. Its extracellular domain has a variable domain-like Ig fold. Loops corresponding to CDRs of antibodies can be substituted with heterologous sequence to confer different binding properties. CTLA-4 molecules engineered to have different binding specificities are also known as Evibodies. For further details see Journal of Immunological Methods 248 (1-2), 31-45 (2001)

Lipocalins are a family of extracellular proteins which transport small hydrophobic molecules such as steroids, bilins, retinoids and lipids. They have a rigid β-sheet secondary structure with a number of loops at the open end of the conical structure which can be engineered to bind to different target antigens. Anticalins are between 160-180 amino acids in size, and are derived from lipocalins. For further details see Biochim Biophys Acta 1482: 337-350 (2000), U.S. Pat. No. 7,250,297B1 and US20070224633

An affibody is a scaffold derived from Protein A of Staphylococcus aureus which can be engineered to bind to antigen. The domain consists of a three-helical bundle of approximately 58 amino acids. Libraries have been generated by randomisation of surface residues. For further details see Protein Eng. Des. Sel. 17, 455-462 (2004) and EP1641818A1

Avimers are multidomain proteins derived from the A-domain scaffold family. The native domains of approximately 35 amino acids adopt a defined disulphide bonded structure. Diversity is generated by shuffling of the natural variation exhibited by the family of A-domains. For further details see Nature Biotechnology 23(12), 1556-1561 (2005) and Expert Opinion on Investigational Drugs 16(6), 909-917 (June 2007)

A transferrin is a monomeric serum transport glycoprotein. Transferrins can be engineered to bind different target antigens by insertion of peptide sequences in a permissive surface loop. Examples of engineered transferrin scaffolds include the Trans-body. For further details see J. Biol. Chem. 274, 24066-24073 (1999).

Designed Ankyrin Repeat Proteins (DARPins) are derived from Ankyrin which is a family of proteins that mediate attachment of integral membrane proteins to the cytoskeleton. A single ankyrin repeat is a 33 residue motif consisting of two α-helices and a β-turn. They can be engineered to bind different target antigens by randomising residues in the first α-helix and a β-turn of each repeat. Their binding interface can be increased by increasing the number of modules (a method of affinity maturation). For further details see J. Mol. Biol. 332, 489-503 (2003), PNAS 100(4), 1700-1705 (2003) and J. Mol. Biol. 369, 1015-1028 (2007) and US20040132028A1.

Fibronectin is a scaffold which can be engineered to bind to antigen. Adnectins consists of a backbone of the natural amino acid sequence of the 10th domain of the 15 repeating units of human fibronectin type III (FN3). Three loops at one end of the β-sandwich can be engineered to enable an Adnectin to specifically recognize a therapeutic target of interest. For further details see Protein Eng. Des. Sel. 18, 435-444 (2005), US20080139791, WO2005056764 and U.S. Pat. No. 6,818,418B1.

Peptide aptamers are combinatorial recognition molecules that consist of a constant scaffold protein, typically thioredoxin (TrxA) which contains a constrained variable peptide loop inserted at the active site. For further details see Expert Opin. Biol. Ther. 5, 783-797 (2005).

Microbodies are derived from naturally occurring microproteins of 25-50 amino acids in length which contain 3-4 cysteine bridges—examples of microproteins include KalataB1 and conotoxin and knottins. The microproteins have a loop which can be engineered to include up to 25 amino acids without affecting the overall fold of the microprotein. For further details of engineered knottin domains, see WO2008098796.

Other epitope binding domains include proteins which have been used as a scaffold to engineer different target antigen binding properties include human γ-crystallin and human ubiquitin (affilins), kunitz type domains of human protease inhibitors, PDZ-domains of the Ras-binding protein AF-6, scorpion toxins (charybdotoxin), C-type lectin domain (tetranectins) are reviewed in Chapter 7—Non-Antibody Scaffolds from Handbook of Therapeutic Antibodies (2007, edited by Stefan Dubel) and Protein Science 15:14-27 (2006). Epitope binding domains of the present invention could be derived from any of these alternative protein domains.

As used herein, the term “antigen-binding site” refers to a site on a protein which is capable of specifically binding to antigen, this may be a single domain, for example an epitope-binding domain, or it may be paired VH/VL domains as can be found on a standard antibody. In some aspects of the invention single-chain Fv (ScFv) domains can provide antigen-binding sites.

The terms “mAbdAb” and dAbmAb” are used herein to refer to antigen-binding proteins of the present invention. The two terms can be used interchangeably, and are intended to have the same meaning as used herein.

The term “antigen binding protein” as used herein refers to antibodies, antibody fragments, for example a domain antibody (dAb), ScFv, FAb, FAb₂, and other protein constructs which are capable of binding to IL-13. Antigen binding molecules may comprise at least one Ig variable domain, for example antibodies, domain antibodies, Fab, Fab′, F(ab′)₂, Fv, ScFv, diabodies, mAbdAbs, affibodies, heteroconjugate antibodies or bispecifics. In one embodiment the antigen binding molecule is an antibody. In another embodiment the antigen binding molecule is a dAb, i.e. an immunoglobulin single variable domain such as a VH, VHH or VL that specifically binds an antigen or epitope independently of a different V region or domain. Antigen binding molecules may be capable of binding to two targets, I.e. they may be dual targeting proteins. Antigen binding molecules may be a combination of antibodies and antigen binding fragments such as for example, one or more domain antibodies and/or one or more ScFvs linked to a monoclonal antibody. Antigen binding molecules may also comprise a non-Ig domain for example a domain which is a derivative of a scaffold selected from the group consisting of CTLA-4 (Evibody); lipocalin; Protein A derived molecules such as Z-domain of Protein A (Affibody, SpA), A-domain (Avimer/Maxibody); Heat shock proteins such as GroEI and GroES; transferrin (trans-body); ankyrin repeat protein (DARPin); peptide aptamer; C-type lectin domain (Tetranectin); human γ-crystallin and human ubiquitin (affilins); PDZ domains; scorpion toxinkunitz type domains of human protease inhibitors; and fibronectin (adnectin); which has been subjected to protein engineering in order to obtain binding to IL-13. As used herein “antigen binding protein” will be capable of antagonising and/or neutralising human IL-13. In addition, an antigen binding protein may block IL-13 activity by binding to IL-13 and preventing a natural ligand from binding and/or activating the receptor.

As used herein “IL-13 antagonist” includes any compound capable of reducing and or eliminating at least one activity of IL-13. By way of example, an IL-13 antagonist may bind to IL-13 and that binding may directly reduce or eliminate IL-13 activity or it may work indirectly by blocking at least one ligand from binding the receptor.

As used herein “IL-4 antagonist” includes any compound capable of reducing and or eliminating at least one activity of IL-4. By way of example, an IL-4 antagonist may bind to IL-4 and that binding may directly reduce or eliminate IL-4 activity or it may work indirectly by blocking at least one ligand from binding the receptor.

As used herein “IL-5 antagonist” includes any compound capable of reducing and or eliminating at least one activity of IL-5. By way of example, an IL-5 antagonist may bind to IL-5 and that binding may directly reduce or eliminate IL-5 activity or it may work indirectly by blocking at least one ligand from binding the receptor.

DETAILED DESCRIPTION OF THE INVENTION

In one embodiment the antigen binding proteins of the present invention comprise a heavy chain variable region containing a CDRH3 selected from the list consisting of SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO:8 and SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO:14 and SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17 and SEQ ID NO: 18 and a suitable CDRH1 and CDRH2, paired with a light chain variable region containing a suitable CDRL1, CDRL2 and CDRL3 to form an antigen binding Fv unit which binds to human IL-13. In one embodiment the antigen binding proteins of the present invention neutralise the activity of human IL-13

In one aspect of this embodiment the CDRH1 as set out in SEQ ID NO: 1 or SEQ ID NO: 60, or SEQ ID NO:61 and CDRH2 as set out in SEQ ID NO: 2 are also present in the heavy chain variable region. In a further aspect of this embodiment the CDRHL1 as set out in SEQ ID NO: 19, CDRL2 as set out in SEQ ID NO:20 and CDRL3 as set out in SEQ ID NO: 21 are also present in the light chain variable region.

In another aspect the antigen binding protein binds to human IL-13 with high affinity as measured by Biacore of 10 nM or less, and more particularly 2 nM or less, for example between about 0.8 nM and 2 nM, 1 nM or less, or 100 pM or less, for example between about 20 pM and about 100 pM or between about 20 pM and about 80 pM, or between about 20 pM and about 60 pM. In one such embodiment, this is measured by Biacore with the antigen binding protein being captured on the biosensor chip, for example as set out in Example 3.

The heavy chain variable regions of the present invention may be formatted together with light chain variable regions to allow binding to human IL-13, in the conventional immunoglobulin manner (for example, human IgG, IgA, IgM etc.) or in any other “antibody-like” format that binds to human IL-13 (for example, single chain Fv, diabodies, Tandabs™ etc (for a summary of alternative “antibody” formats see Holliger and Hudson, Nature Biotechnology, 2005, Vol 23, No. 9, 1126-1136)).

The antigen binding proteins of the present invention are derived from the murine antibody having the variable regions as described in SEQ ID NO:58 and SEQ ID NO:59 or non-murine equivalents thereof, such as rat, human, chimeric or humanised variants thereof, for example they are derived from the humanised antibody having the heavy and light chains as described in SEQ ID NO:22 and SEQ ID NO:24.

In one aspect of the invention there is provided an antigen binding protein, for example an antibody which binds human IL-13 and which comprises variants of the CDRH3 SIYDDYHYDDYYAMDY (SEQ ID NO: 3), wherein CDRH3 is substituted by the alternative amino acids set out below at one or more of the following positions (using Kabat numbering):

-   a) S95 in position 1 is substituted for tryptophan (W) -   b) 196 in position 2 is substituted for valine (V) -   c) Y97 in position 3 is substituted for phenylalanine (F) -   d) D98 in position 4 is substituted for glutamine (E) -   e) H100A in position 7 is substituted for alanine (A), glutamic acid     (E), glutamine (Q), Arginine (R), Serine (S), threonine (T) or     valine (V), and -   f) Y100B in position 8 is substituted for alanine (A), isoleucine,     (I), tryptophan (W) or valine (V).

In another aspect of the invention there is provided an antigen binding protein, for example an antibody which binds human IL-13 and which comprises the CDRH3 set out in SEQ ID NO: 3, wherein CDRH3 comprises one or more of the following substitutions: S95W, I96V, Y97F, D98E, H100A_A, H100A_E, H100A_Q, H100A_R, H100A_S, H100A_T, H100A_V, Y100B_A, Y100B_I, Y100B_W, and Y100B_V.

In one aspect the antigen binding protein of the present invention, for example the antibody of the present invention, comprises a CDRH3 sequence selected from those set out in SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO:8 and SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO:14 and SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17 and SEQ ID NO: 18. Such antigen binding proteins may further comprise the following CDR sequences:

CDRH1: selected from SEQ ID NO:1, 60 and 61,

CDRH2: SEQ ID NO: 2; CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.

In one embodiment the antigen binding protein comprises the following CDRs:

CDRH1: SEQ ID NO:1, CDRH2: SEQ ID NO:2; CDRH3: SEQ ID NO:18 CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.

In another embodiment the antigen binding protein comprises the following CDRs:

CDRH1: SEQ ID NO:1, CDRH2: SEQ ID NO:2; CDRH3: SEQ ID NO:17 CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.

In another embodiment the antigen binding protein comprises the following CDRs:

CDRH1: SEQ ID NO:1, CDRH2: SEQ ID NO:2; CDRH3: SEQ ID NO:16 CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.

In another embodiment the antigen binding protein comprises the following CDRs:

CDRH1: SEQ ID NO:1, CDRH2: SEQ ID NO:2; CDRH3: SEQ ID NO:15 CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.

Throughout this specification, amino acid residues in antibody sequences are numbered according to the Kabat scheme. Similarly, the terms “CDR”, “CDRL1”, “CDRL2”, “CDRL3”, “CDRH1”, “CDRH2”, “CDRH3”, unless otherwise indicated (e.g. CDRH3 as set out in SEQ ID NO:60 and 61), follow the Kabat numbering system as set forth in Kabat et al; “Sequences of proteins of Immunological Interest” NIH, 1987.

In another aspect of the invention there is provided an antigen binding protein, such as a humanised antibody or antigen binding fragment thereof, comprising a heavy chain having the sequence selected from SEQ ID NO: 26, SEQ ID NO: 28, SEQ ID NO: 30, SEQ ID NO: 32, SEQ ID NO: 34, SEQ ID NO: 36, SEQ ID NO: 38, SEQ ID NO: 40, SEQ ID NO: 42, SEQ ID NO: 44, SEQ ID NO: 46, SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52, SEQ ID NO: 54, SEQ ID NO: 88, SEQ ID NO: 89, SEQ ID NO: 90 and SEQ ID NO: 91; and the light chain of SEQ ID NO:24.

The invention provides an antigen binding protein, such as a humanised antibody or antigen binding fragment thereof, comprising a heavy chain selected from SEQ ID NO: 26, SEQ ID NO: 28, SEQ ID NO: 30, SEQ ID NO: 32, SEQ ID NO: 34, SEQ ID NO: 36, SEQ ID NO: 38, SEQ ID NO: 40, SEQ ID NO: 42, SEQ ID NO: 44, SEQ ID NO: 46, SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52, SEQ ID NO: 54, SEQ ID NO: 88, SEQ ID NO: 89, SEQ ID NO: 90.

The invention also provides an antigen binding protein, such as a humanised antibody or antigen binding fragment thereof, comprising a light chain selected from SEQ ID NO: 108, SEQ ID NO: 110, SEQ ID NO: 112 and SEQ ID NO: 114.

The invention further provides an antigen binding protein, such as a humanised antibody or antigen binding fragment thereof, comprising a heavy chain having the sequence selected from SEQ ID NO: 26, SEQ ID NO: 28, SEQ ID NO: 30, SEQ ID NO: 32, SEQ ID NO: 34, SEQ ID NO: 36, SEQ ID NO: 38, SEQ ID NO: 40, SEQ ID NO: 42, SEQ ID NO: 44, SEQ ID NO: 46, SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52, SEQ ID NO: 54, SEQ ID NO: 88, SEQ ID NO: 89, SEQ ID NO: 90 and SEQ ID NO: 91; and the light chain of SEQ ID NO: 108, SEQ ID NO: 110, SEQ ID NO: 112 and SEQ ID NO: 114.

In one embodiment the antigen binding protein of the present invention comprises an antibody comprising a heavy chain selected from SEQ ID NO: 26, SEQ ID NO: 28, SEQ ID NO: 30, SEQ ID NO: 32, SEQ ID NO: 34, SEQ ID NO: 36, SEQ ID NO: 38, SEQ ID NO: 40, SEQ ID NO: 42, SEQ ID NO: 44, SEQ ID NO: 46, SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52, SEQ ID NO: 54, SEQ ID NO: 88, SEQ ID NO: 89, SEQ ID NO: 90 and SEQ ID NO: 91 and a light chain selected from SEQ ID NO:24, SEQ ID NO: 108, SEQ ID NO: 110, SEQ ID NO: 112 and SEQ ID NO: 114.

In one embodiment the antigen binding protein of the present invention comprises a heavy chain selected from SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52 and SEQ ID NO: 54; and a light chain selected from SEQ ID NO: 24, SEQ ID NO: 108, SEQ ID NO:110, SEQ ID NO:112 and SEQ ID NO:114, for example the antigen binding protein comprises the heavy chain of SEQ ID NO: 48 and the light chain of SEQ ID NO:24, or the heavy chain of SEQ ID NO: 50 and the light chain of SEQ ID NO:24, or the heavy chain of SEQ ID NO: 52 and the light chain of SEQ ID NO:24, or the heavy chain of SEQ ID NO: 54 and the light chain of SEQ ID NO:24, or the heavy chain of SEQ ID NO: 88 and the light chain of SEQ ID NO:24 or the heavy chain of SEQ ID NO: 89 and the light chain of SEQ ID NO:24, or the heavy chain of SEQ ID NO: 90 and the light chain of SEQ ID NO:24, or the heavy chain of SEQ ID NO: 91 and the light chain of SEQ ID NO:24, or the heavy chain of SEQ ID NO: 48 and the light chain of SEQ ID NO:108, or the heavy chain of SEQ ID NO: 50 and the light chain of SEQ ID NO:108, or the heavy chain of SEQ ID NO: 52 and the light chain of SEQ ID NO:108, or the heavy chain of SEQ ID NO: 54 and the light chain of SEQ ID NO:108, or the heavy chain of SEQ ID NO: 88 and the light chain of SEQ ID NO:108 or the heavy chain of SEQ ID NO: 89 and the light chain of SEQ ID NO:108, or the heavy chain of SEQ ID NO: 90 and the light chain of SEQ ID NO:108, or the heavy chain of SEQ ID NO: 91 and the light chain of SEQ ID NO:108, or the heavy chain of SEQ ID NO: 48 and the light chain of SEQ ID NO:110, or the heavy chain of SEQ ID NO: 50 and the light chain of SEQ ID NO:110, or the heavy chain of SEQ ID NO: 52 and the light chain of SEQ ID NO:110, or the heavy chain of SEQ ID NO: 54 and the light chain of SEQ ID NO:110, or the heavy chain of SEQ ID NO: 88 and the light chain of SEQ ID NO:110 or the heavy chain of SEQ ID NO: 89 and the light chain of SEQ ID NO:110, or the heavy chain of SEQ ID NO: 90 and the light chain of SEQ ID NO:110, or the heavy chain of SEQ ID NO: 91 and the light chain of SEQ ID NO:110.

In one such embodiment the antigen binding protein of the present invention comprises a heavy chain selected from SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52 and SEQ ID NO: 54; and a light chain selected from SEQ ID NO:108 and SEQ ID NO:110, for example the antigen binding protein comprises the heavy chain of SEQ ID NO: 48 and the light chain of SEQ ID NO:108, or the antigen binding protein comprises the heavy chain of SEQ ID NO: 48 and the light chain of SEQ ID NO:110, or the antigen binding protein comprises the heavy chain of SEQ ID NO: 50 and the light chain of SEQ ID NO:108, or the antigen binding protein comprises the heavy chain of SEQ ID NO: 50 and the light chain of SEQ ID NO:110, or the antigen binding protein comprises the heavy chain of SEQ ID NO: 52 and the light chain of SEQ ID NO:108, or the antigen binding protein comprises the heavy chain of SEQ ID NO: 52 and the light chain of SEQ ID NO:110, or the antigen binding protein comprises the heavy chain of SEQ ID NO: 54 and the light chain of SEQ ID NO:108, or the antigen binding protein comprises the heavy chain of SEQ ID NO: 54 and the light chain of SEQ ID NO:110.

The IL-13 antibodies of the present invention may be combined with an IL-4 and/or an IL-5 antagonist, for example an IL-4 antibody or epitope binding domain, and/or an IL-5 antibody or epitope binding domain. These may be administered as a mixture of separate molecules which are administered at the same time i.e. co-administered, or are administered within 24 hours of each other, for example within 20 hours, or within 15 hours or within 12 hours, or within 10 hours, or within 8 hours, or within 6 hours, or within 4 hours, or within 2 hours, or within 1 hour, or within 30 minutes of each other.

In a further embodiment the antagonists are present as one molecule capable of binding to two or more antigens, for example the invention provides an antigen binding protein comprising the IL-13 antibody of the present invention which is capable of binding to IL-13 and which is also capable of binding to IL-4 or which is also capable of binding to IL-5, or which is also capable of binding to IL-4 and IL-5.

In one embodiment the antigen binding protein of the present invention may be a multi-specific antibody which comprises at least CDRH3, and optionally one or more of CDRH1, CDRH2, CDRL1, CDRL2, and CDRL3 of the present invention, which is capable of binding to IL-13 and which is also capable of binding to one or more of IL-4 or IL-5. In one such embodiment, a multi-specific antibody is provided which comprises a CDRH3, or an antigen binding protein as defined herein, and which comprises a further antigen binding site which is capable of binding to IL-4, or IL-5.

One example of an antigen binding protein of the present invention is an antibody specific for IL-13 comprising CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 as defined herein, linked to one or more epitope-binding domains which have specificity for IL-4 or IL-5, for example a bispecific antigen binding protein which is capable of binding to IL-13 and IL-4, or IL-13 and IL-5, or a trispecific antigen binding protein which is capable of binding to IL-13, IL-4 and IL-5.

It will be understood that any of the antigen-binding proteins described herein may be capable of binding two or more antigens simultaneously, for example, as determined by stochiometry analysis by using a suitable assay such as that described in Example 8.

The present invention provides an antigen-binding protein comprising the IL-13 antibody of the present invention which is linked to one or more epitope-binding domains, for example an antigen-binding protein comprising the IL-13 antibody of the present invention linked to an epitope-binding domain which is capable of binding to IL-4, or an antigen-binding protein comprising the IL-13 antibody of the present invention linked to an epitope-binding domain which is capable of binding to IL-5, or an antigen-binding protein comprising the IL-13 antibody of the present invention linked to a first epitope-binding domain which is capable of binding to IL-4 and a second epitope-binding domain which is capable of binding to IL-5.

The epitope-binding domain may be attached to the c-terminus or the n-terminus of the heavy chain of the IL-13 antibody or the c-terminus or n-terminus of the light chain of the IL-13 antibody.

Examples of suitable linkers include amino acid sequences which may be from 1 amino acid to 150 amino acids in length, or from 1 amino acid to 140 amino acids, for example, from 1 amino acid to 130 amino acids, or from 1 to 120 amino acids, or from 1 to 80 amino acids, or from 1 to 50 amino acids, or from 1 to 20 amino acids, or from 1 to 10 amino acids, or from 5 to 18 amino acids. Such sequences may have their own tertiary structure, for example, a linker of the present invention may comprise a single variable domain. The size of a linker in one embodiment is equivalent to a single variable domain. Suitable linkers may be of a size from 1 to 20 angstroms, for example less than 15 angstroms, or less than 10 angstroms, or less than 5 angstroms.

In one embodiment of the present invention at least one of the epitope binding domains is directly attached to the IL-13 antibody with a linker comprising from 1 to 150 amino acids, for example 1 to 20 amino acids, for example 1 to 10 amino acids.

Such linkers may be selected from any one of those set out in SEQ ID NO:82-87, 92 to 93. or multiples of such linkers.

Linkers of use in the antigen-binding proteins of the present invention may comprise alone or in addition to other linkers, one or more sets of GS residues, for example ‘GSTVAAPS’ (SEQ ID NO: 92) or TVAAPSGS' (SEQ ID NO: 87) or ‘GSTVAAPSGS’ (SEQ ID NO: 93). In one embodiment the linker comprises SEQ ID NO: 83.

In one embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘(PAS)_(n)(GS)_(m)’. In another embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘(GGGGS)_(n)(GS)_(m)’. In another embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘(TVAAPS)_(n)(GS)_(m)’. In another embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘(GS)_(m)(TVAAPSGS)_(n)’. In another embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘(PAVPPP)_(n)(GS)_(m)’. In another embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘(TVSDVP)_(n)(GS)_(m)’. In another embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘(TGLDSP)_(n)(GS)_(m)’. In all such embodiments, n=1-10, and m=0-4.

Examples of such linkers include (PAS)_(n)(GS)_(m) wherein n=1 and m=1, (PAS)_(n)(GS)_(m) wherein n=2 and m=1, (PAS)_(n)(GS)_(m) wherein n=3 and m=1, (PAS)_(n)(GS)_(m) wherein n=4 and m=1, (PAS)_(n)(GS)_(m) wherein n=2 and m=0, (PAS)_(n)(GS)_(m) wherein n=3 and m=0, (PAS)_(n)(GS)_(m) wherein n=4 and m=0.

Examples of such linkers include (GGGGS)_(n)(GS)_(m) wherein n=1 and m=1, (GGGGS)_(n)(GS)_(m) wherein n=2 and m=1, (GGGGS)_(n)(GS)_(m) wherein n=3 and m=1, (GGGGS)_(n)(GS)_(m) wherein n=4 and m=1, (GGGGS)_(n)(GS)_(m) wherein n=2 and m=0, (GGGGS)_(n)(GS)_(m) wherein n=3 and m=0, (GGGGS)_(n)(GS)_(m) wherein n=4 and m=0.

Examples of such linkers include (TVAAPS)_(n)(GS)_(m) wherein n=1 and m=1 (SEQ ID NO:87), (TVAAPS)_(n)(GS)_(m) wherein n=2 and m=1 (SEQ ID NO:145), (TVAAPS)_(n)(GS)_(m) wherein n=3 and m=1 (SEQ ID NO:146), (TVAAPS)_(n)(GS)_(m) wherein n=4 and m=1, (TVAAPS)_(n)(GS)_(m) wherein n=2 and m=0, (TVAAPS)_(n)(GS)_(m) wherein n=3 and m=0, (TVAAPS)_(n)(GS)_(m) wherein n=4 and m=0.

Examples of such linkers include (GS)_(m)(TVAAPSGS)_(n) wherein n=1 and m=1 (SEQ ID NO:139), (GS)_(m)(TVAAPSGS)_(n) wherein n=2 and m=1 (SEQ ID NO:140), (GS)_(m)(TVAAPSGS)_(n) wherein n=3 and m=1 (SEQ ID NO:141), or (GS)_(m)(TVAAPSGS)_(n) wherein n=4 and m=1 (SEQ ID NO:142), (GS)_(m)(TVAAPSGS)_(n) wherein n=5 and m=1 (SEQ ID NO:143), (GS)_(m)(TVAAPSGS)_(n) wherein n=6 and m=1 (SEQ ID NO:144), (GS)_(m)(TVAAPSGS)_(n) wherein n=1 and m=0 (SEQ ID NO:87), (GS)_(m)(TVAAPSGS)_(n) wherein n=2 and m=10, (GS)_(m)(TVAAPSGS)_(n) wherein n=3 and m=0, or (GS)_(m)(TVAAPSGS)_(n) wherein n=0.

Examples of such linkers include (PAVPPP)_(n)(GS)_(m) wherein n=1 and m=1, (PAVPPP)_(n)(GS)_(m) wherein n=2 and m=1 (SEQ ID NO: 65), (PAVPPP)_(n)(GS)_(m) wherein n=3 and m=1, (PAVPPP)_(n)(GS)_(m) wherein n=4 and m=1, (PAVPPP)_(n)(GS)_(m) wherein n=2 and m=0, (PAVPPP)_(n)(GS)_(m) wherein n=3 and m=0, (PAVPPP)_(n)(GS)_(m) wherein n=4 and m=0.

Examples of such linkers include (TVSDVP)_(n)(GS)_(m) wherein n=1 and m=1 (SEQ ID NO: 67), (TVSDVP)_(n)(GS)_(m) wherein n=2 and m=1, (TVSDVP)_(n)(GS)_(m) wherein n=3 and m=1, (TVSDVP)_(n)(GS)_(m) wherein n=4 and m=1, (TVSDVP)_(n)(GS)_(m) wherein n=2 and m=0, (TVSDVP)_(n)(GS)_(m) wherein n=3 and m=0, (TVSDVP)_(n)(GS)_(m) wherein n=4 and m=0.

Examples of such linkers include (TGLDSP)_(n)(GS)_(m) wherein n=1 and m=1, (TGLDSP)_(n)(GS)_(m) wherein n=2 and m=1, (TGLDSP)_(n)(GS)_(m) wherein n=3 and m=1, (TGLDSP)_(n)(GS)_(m) wherein n=4 and m=1, (TGLDSP)_(n)(GS)_(m) wherein n=2 and m=0, (TGLDSP)_(n)(GS)_(m) wherein n=3 and m=0, (TGLDSP)_(n)(GS)_(m) wherein n=4 and m=0.

In another embodiment there is no linker between the epitope binding domain and the IL-13 antibody. In another embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘TVAAPS’ (SEQ ID NO: 83). In another embodiment the epitope binding domain, is linked to the IL-13 antibody by the linker TVAAPSGS' (SEQ ID NO: 87). In another embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘GS’. In another embodiment the epitope binding domain is linked to the IL-13 antibody by the linker ‘ASTKGPT’ (SEQ ID NO: 84).

Epitope-binding domains of use in the present invention are domains that specifically bind an antigen or epitope independently of a different V region or domain, this may be a domain antibody or may be a non-Immunoglobulin domain, for example a domain which is a derivative of a scaffold selected from the group consisting of CTLA-4 (Evibody); lipocalin; Protein A derived molecules such as Z-domain of Protein A (Affibody, SpA), A-domain (Avimer/Maxibody); Heat shock proteins such as GroEI and GroES; transferrin (trans-body); ankyrin repeat protein (DARPin); peptide aptamer; C-type lectin domain (Tetranectin); human γ-crystallin and human ubiquitin (affilins); PDZ domains; scorpion toxinkunitz type domains of human protease inhibitors; and fibronectin (adnectin); which has been subjected to protein engineering in order to obtain binding to a ligand other than the natural ligand. In one embodiment this may be an domain antibody or other suitable domains such as a domain selected from the group consisting of CTLA-4, lipocallin, SpA, an Affibody, an avimer, GroEI, transferrin, GroES and fibronectin. In one embodiment this may be selected from an immunoglobulin single variable domain, an Affibody, an ankyrin repeat protein (DARPin) and an adnectin. In another embodiment this may be selected from an Affibody, an ankyrin repeat protein (DARPin) and an adnectin. In another embodiment this may be a domain antibody, for example a domain antibody selected from a human, camelid (nanobody), or shark (NARV) domain antibody.

Examples of such antigen-binding proteins include the IL-13 antibodies of the present invention which have an epitope binding domain which is an IL-4 antagonist attached to the c-terminus or the n-terminus of the heavy chain or the c-terminus. Examples include an antigen binding protein comprising the heavy chain sequence set out in SEQ ID NO: 26, SEQ ID NO: 28, SEQ ID NO: 30, SEQ ID NO: 32, SEQ ID NO: 34, SEQ ID NO: 36, SEQ ID NO: 38, SEQ ID NO: 40, SEQ ID NO: 42, SEQ ID NO: 44, SEQ ID NO: 46, SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52, SEQ ID NO: 54, SEQ ID NO: 98, SEQ ID NO: 100, SEQ ID NO:102, SEQ ID NO:104, SEQ ID NO:106 or SEQ ID NO: 117-138, and the light chain sequence set out in SEQ ID NO: 24, SEQ ID NO: 108, SEQ ID NO: 110, SEQ ID NO: 112 or SEQ ID NO: 114, wherein one or both of the Heavy and Light chain further comprise one or more epitope-binding domains which is capable of antagonising IL-4, for example single variable domains which are capable of binding to IL-4. Such epitope-binding domains can be selected from those set out in SEQ ID NO: 78-81 and 94.

In one embodiment the antigen binding constructs of the present invention comprise the heavy chain sequence of SEQ ID NO: 62 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 64 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 66 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 68 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 70 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 72 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO:74 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 76 and the light chain sequence of SEQ ID NO: 24.

In one embodiment the antigen binding constructs of the present invention comprise the heavy chain sequence of SEQ ID NO: 94 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 96 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 98 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 100 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 102 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO: 104 and the light chain sequence of SEQ ID NO: 24, or the heavy chain sequence of SEQ ID NO:106 and the light chain sequence of SEQ ID NO: 24.

In one embodiment the antigen binding constructs of the present invention comprise the heavy chain sequence of SEQ ID NO: 62 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 64 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 66 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 68 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 70 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 72 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO:74 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 76 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 62 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 64 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 66 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 68 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 70 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 72 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO:74 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 76 and the light chain sequence of SEQ ID NO: 110.

In one embodiment the antigen binding constructs of the present invention comprise the heavy chain sequence of SEQ ID NO: 96 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 98 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 100 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 102 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 104 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 106 and the light chain sequence of SEQ ID NO: 108, or the heavy chain sequence of SEQ ID NO: 96 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 98 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 100 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 102 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 104 and the light chain sequence of SEQ ID NO: 110, or the heavy chain sequence of SEQ ID NO: 106 and the light chain sequence of SEQ ID NO: 110.

In one embodiment the IL-13 antibody heavy chain is selected from those set out in SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52 and SEQ ID NO: 54. In another embodiment the heavy chain is selected from those set out in SEQ ID NO:88-91, SEQ ID NO:96-106, and SEQ ID NO:117-138. In one such embodiment the heavy chain is selected from SEQ ID NO:96, SEQ ID NO: 98, SEQ ID NO:100, SEQ ID NO:102, SEQ ID NO:104 and SEQ ID NO:106.

In one embodiment the antigen-binding protein will comprise an anti-IL-13 antibody linked to an epitope binding domain which is a IL-5 antagonist, wherein the anti-IL-13 antibody comprises the CDRH3 selected from those set out in SEQ ID NO: 3-18, for example SEQ ID NO: 15-18 and the light chain sequence of SEQ ID NO: 24.

Examples include an antigen binding protein comprising the heavy chain sequence set out in SEQ ID NO: 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52 or 54 and the light chain sequence set out in SEQ ID NO: 24 wherein one or both of the Heavy and Light chain further comprise one or more epitope-binding domains which is capable of antagonising IL-5, for example immunoglobulin single variable domains which are capable of binding to IL-5.

In a further embodiment, the antigen binding protein will comprise the heavy chain sequence set out in SEQ ID NO: 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52 or 54 and the light chain sequence set out in SEQ ID NO: 24 wherein one or both of the Heavy and Light chain further comprise one or more epitope-binding domains which are capable of antagonising IL-4 for example immunoglobulin single variable domains which are capable of binding to IL-4, and one or more epitope-binding domains which are capable of antagonising IL-5, for example immunoglobulin single variable domains which are capable of binding to IL-5.

In one embodiment, the antigen-binding protein of the present invention comprises at least one epitope binding domain, which is capable of binding human serum albumin.

In one embodiment, there are at least 3 antigen-binding sites, for example there are 4, or 5 or 6 or 8 or 10 antigen-binding sites and the antigen-binding protein is capable of binding at least 3 or 4 or 5 or 6 or 8 or 10 antigens, for example it is capable of binding 3 or 4 or 5 or 6 or 8 or 10 antigens simultaneously.

In one embodiment, a first epitope binding domain is linked to the protein scaffold and a second epitope binding domain is linked to the first epitope binding domain, for example where the protein scaffold is an IgG scaffold, a first epitope binding domain may be linked to the c-terminus of the heavy chain of the IgG scaffold, and that epitope binding domain can be linked at its c-terminus to a second epitope binding domain, or for example a first epitope binding domain may be linked to the c-terminus of the light chain of the IgG scaffold, and that first epitope binding domain may be further linked at its c-terminus to a second epitope binding domain, or for example a first epitope binding domain may be linked to the n-terminus of the light chain of the IgG scaffold, and that first epitope binding domain may be further linked at its n-terminus to a second epitope binding domain, or for example a first epitope binding domain may be linked to the n-terminus of the heavy chain of the IgG scaffold, and that first epitope binding domain may be further linked at its n-terminus to a second epitope binding domain.

When the epitope-binding domain is a domain antibody, some domain antibodies may be suited to particular positions within the scaffold.

Immunoglobulin single variable domains of use in the present invention can be linked at the C-terminal end of the heavy chain and/or the light chain of the IL-13 mAb. In addition some immunoglobulin single variable domains can be linked to the C-terminal ends of both the heavy chain and the light chain of conventional antibodies.

In constructs where the N-terminus of immunoglobulin single variable domains are fused to an antibody constant domain (either C_(H)3 or CL), a peptide linker may help the immunoglobulin single variable domain to bind to antigen. Indeed, the N-terminal end of a dAb is located closely to the CDRs involved in antigen-binding activity. Thus a short peptide linker acts as a spacer between the epitope-binding domain, and the constant domain of the antibody, which may allow the dAb CDRs to more easily reach the antigen, which may therefore bind with high affinity.

The surroundings in which immunoglobulin single variable domains are linked to the IgG will differ depending on which antibody chain they are fused to:

When fused at the C-terminal end of the antibody light chain, each immunoglobulin single variable domain is expected to be located in the vicinity of the antibody hinge and the Fc portion. It is likely that such immunoglobulin single variable domains will be located far apart from each other. In conventional antibodies, the angle between Fab fragments and the angle between each Fab fragment and the Fc portion can vary quite significantly. It is likely that—with mAbdAbs—the angle between the Fab fragments will not be widely different, whilst some angular restrictions may be observed with the angle between each Fab fragment and the Fc portion.

When fused at the C-terminal end of the antibody heavy chain, each immunoglobulin single variable domain is expected to be located in the vicinity of the C_(H)3 domains of the Fc portion. This is not expected to impact on the Fc binding properties to Fc receptors (e.g. FcγRI, II, III an FcRn) as these receptors engage with the C_(H)2 domains (for the FcγRI, II and III class of receptors) or with the hinge between the C_(H)2 and C_(H)3 domains (e.g. FcRn receptor). Another feature of such antigen-binding proteins is that both immunoglobulin single variable domains are expected to be spatially close to each other and provided that flexibility is provided by provision of appropriate linkers, these immunoglobulin single variable domains may even form homodimeric species, hence propagating the ‘zipped’ quaternary structure of the Fc portion, which may enhance stability of the construct.

Such structural considerations can aid in the choice of the most suitable position to link an epitope-binding domain, for example an immunoglobulin single variable domain, on to an antibody.

The size of the antigen, its localization (in blood or on cell surface), its quaternary structure (monomeric or multimeric) can vary. Conventional antibodies are naturally designed to function as adaptor constructs due to the presence of the hinge region, wherein the orientation of the two antigen-binding sites at the tip of the Fab fragments can vary widely and hence adapt to the molecular feature of the antigen and its surroundings. In contrast immunoglobulin single variable domains linked to an antibody with no hinge region, may have less structural flexibility either directly or indirectly.

Understanding the solution state and mode of binding at the immunoglobulin single variable domain is also helpful. Evidence has accumulated that in vitro human dAbs can predominantly exist in monomeric, homo-dimeric or multimeric forms in solution (Reiter et al. (1999) J Mol Biol 290 p 685-698; Ewert et al (2003) J Mol Biol 325, p 531-553, Jespers et al (2004) J Mol Biol 337 p 893-903; Jespers et al (2004) Nat Biotechnol 22 p 1161-1165; Martin et al (1997) Protein Eng. 10 p 607-614; Sepulvada et al (2003) J Mol Biol 333 p 355-365). This is fairly reminiscent to multimerisation events observed in vivo with Ig domains such as Bence-Jones proteins (which are dimers of immunoglobulin light chains (Epp et al (1975) Biochemistry 14 p 4943-4952; Huan et al (1994) Biochemistry 33 p 14848-14857; Huang et al (1997) Mol immunol 34 p 1291-1301) and amyloid fibers (James et al. (2007) J Mol. Biol. 367:603-8).

For example, it may be desirable to link dAbs that tend to dimerise in solution to the C-terminal end of the Fc portion in preference to the C-terminal end of the light chain as linking to the C-terminal end of the Fc will allow those dAbs to dimerise in the context of the antigen-binding protein of the invention.

The antigen-binding proteins of the present invention may comprise antigen-binding sites specific for a single antigen, or may have antigen-binding sites specific for two or more antigens, or for two or more epitopes on a single antigen, or there may be antigen-binding sites each of which is specific for a different epitope on the same or different antigens.

The antigen binding proteins of the invention may comprise heavy chain variable regions and light chain variable regions of the invention which may be formatted into the structure of a natural antibody or functional fragment or equivalent thereof. An antigen binding protein of the invention may therefore comprise the VH regions of the invention formatted into a full length antibody, a (Fab′)₂ fragment, a Fab fragment, or equivalent thereof (such as scFV, bi- tri- or tetra-bodies, Tandabs etc.), when paired with an appropriate light chain. The antibody may be an IgG1, IgG2, IgG3, or IgG4; or IgM; IgA, IgE or IgD or a modified variant thereof. The constant domain of the antibody heavy chain may be selected accordingly. The light chain constant domain may be a kappa or lambda constant domain. Furthermore, the antigen binding protein may comprise modifications of all classes e.g. IgG dimers, Fc mutants that no longer bind Fc receptors or mediate C1q binding. The antigen binding protein may also be a chimeric antibody of the type described in WO86/01533 which comprises an antigen binding region and a non-immunoglobulin region.

The constant region is selected according to any functionality required. An IgG1 may demonstrate lytic ability through binding to complement and/or will mediate ADCC (antibody dependent cell cytotoxicity). An IgG4 can be used if a non-cytotoxic blocking antibody is required. However, IgG4 antibodies can demonstrate instability in production and therefore an alternative is to modify the generally more stable IgG1. Suggested modifications are described in EP0307434, for example mutations at positions 235 and 237. The invention therefore provides a lytic or a non-lytic form of an antigen binding protein, for example an antibody according to the invention.

In certain forms the antibody of the invention is a full length (e.g. H2L2 tetramer) lytic or non-lytic IgG1 antibody having any of the heavy chain variable regions described herein. In a further aspect, the invention provides polynucleotides encoding the light and heavy chain variable regions as described herein.

In one embodiment of the invention the antigen-binding site binds to antigen with a Kd of at least about 1 mM, for example a Kd of at least about 10 nM, at least about 1 nM, at least about 500 μM, at least about 200 μM, at least about 100 μM, or at least about 50 μM to each antigen as measured by Biacore™.

In one embodiment of the invention the antigen-binding site binds to antigen with a Kd of at least about 1 mM, for example a Kd of at least about 10 nM, at least about 1 nM, at least about 500 μM, at least about 200 μM, at least about 100 μM, or at least about 50 μM to each antigen as measured by Biacore™.

In one embodiment the invention provides antigen binding proteins which have at least a 2 fold higher affinity, or at least 4 fold higher affinity, or at least 6 fold higher affinity, or at least 8 fold higher affinity, or at least 10 fold higher affinity for human IL-13 as measured by Biacore than the anti-IL=13 antibody comprising the heavy chain sequence set out in SEQ ID NO:22 and the light chain sequence set out in SEQ ID NO:24.

The term “neutralises” and grammatical variations thereof as used throughout the present specification in relation to antigen binding proteins of the invention means that a biological activity of IL-13 is reduced, either totally or partially, in the presence of the antigen binding proteins of the present invention in comparison to the activity of IL-13 in the absence of such antigen binding proteins. Neutralisation may be due to but not limited to one or more of blocking ligand binding, preventing the ligand activating the receptor, down regulating the IL-13 receptor or affecting effector functionality. Levels of neutralisation can be measured in several ways, for example by use of the assays as set out in the examples below, for example in a TF1 assay which may be carried out for example as described in Example 4. The neutralisation of IL-13, IL-4 or both of these cytokines in this assay is measured by assessing the inhibition of TF1 cell proliferation in the presence of neutralising antigen binding protein.

Other methods of assessing neutralisation, for example, by assessing the decreased binding between the IL-13 and its receptor in the presence of neutralising antigen binding protein are known in the art, and include, for example, Biacore assays.

In an alternative aspect of the present invention there is provided antigen binding proteins which have at least substantially equivalent neutralising activity to the antibodies exemplified herein, for example antigen binding proteins which retain the neutralising activity of A1Y100BAlaL1, A1Y100BIleL1, A1Y100BTrpL1 or A1Y100BValL1 in a TF1 cell proliferation assay which can be carried out as set out in Example 4.

The antigen binding proteins, for example antibodies of the present invention may be produced by transfection of a host cell with an expression vector comprising the coding sequence for the antigen binding protein of the invention. An expression vector or recombinant plasmid is produced by placing these coding sequences for the antigen binding protein in operative association with conventional regulatory control sequences capable of controlling the replication and expression in, and/or secretion from, a host cell. Regulatory sequences include promoter sequences, e.g., CMV promoter, and signal sequences which can be derived from other known antibodies. Similarly, a second expression vector can be produced having a DNA sequence which encodes a complementary antigen binding protein light or heavy chain. In certain embodiments this second expression vector is identical to the first except insofar as the coding sequences and selectable markers are concerned, so to ensure as far as possible that each polypeptide chain is functionally expressed. Alternatively, the heavy and light chain coding sequences for the antigen binding protein may reside on a single vector. A selected host cell is co-transfected by conventional techniques with both the first and second vectors (or simply transfected by a single vector) to create the transfected host cell of the invention comprising both the recombinant or synthetic light and heavy chains. The transfected cell is then cultured by conventional techniques to produce the engineered antigen binding protein of the invention. The antigen binding protein which includes the association of both the recombinant heavy chain and/or light chain is screened from culture by appropriate assay, such as ELISA or RIA. Similar conventional techniques may be employed to construct other antigen binding proteins.

Suitable vectors for the cloning and subcloning steps employed in the methods and construction of the compositions of this invention may be selected by one of skill in the art. For example, the conventional pUC series of cloning vectors may be used. One vector, pUC19, is commercially available from supply houses, such as Amersham (Buckinghamshire, United Kingdom) or Pharmacia (Uppsala, Sweden). Additionally, any vector which is capable of replicating readily, has an abundance of cloning sites and selectable genes (e.g., antibiotic resistance), and is easily manipulated may be used for cloning. Thus, the selection of the cloning vector is not a limiting factor in this invention.

The expression vectors may also be characterized by genes suitable for amplifying expression of the heterologous DNA sequences, e.g., the mammalian dihydrofolate reductase gene (DHFR). Other vector sequences include a poly A signal sequence, such as from bovine growth hormone (BGH) and the betaglobin promoter sequence (betaglopro). The expression vectors useful herein may be synthesized by techniques well known to those skilled in this art.

The components of such vectors, e.g. replicons, selection genes, enhancers, promoters, signal sequences and the like, may be obtained from commercial or natural sources or synthesized by known procedures for use in directing the expression and/or secretion of the product of the recombinant DNA in a selected host. Other appropriate expression vectors of which numerous types are known in the art for mammalian, bacterial, insect, yeast, and fungal expression may also be selected for this purpose.

The present invention also encompasses a cell line transfected with a recombinant plasmid containing the coding sequences of the antigen binding proteins of the present invention. Host cells useful for the cloning and other manipulations of these cloning vectors are also conventional. However, cells from various strains of E. coli may be used for replication of the cloning vectors and other steps in the construction of antigen binding proteins of this invention.

Suitable host cells or cell lines for the expression of the antigen binding proteins of the invention include mammalian cells such as NSO, Sp2/0, CHO (e.g. DG44), COS, HEK, a fibroblast cell (e.g., 3T3), and myeloma cells, for example it may be expressed in a CHO or a myeloma cell. Human cells may be used, thus enabling the molecule to be modified with human glycosylation patterns. Alternatively, other eukaryotic cell lines may be employed. The selection of suitable mammalian host cells and methods for transformation, culture, amplification, screening and product production and purification are known in the art. See, e.g., Sambrook et al., cited above.

Bacterial cells may prove useful as host cells suitable for the expression of the recombinant Fabs or other embodiments of the present invention (see, e.g., Plückthun, A., Immunol. Rev., 130:151-188 (1992)). However, due to the tendency of proteins expressed in bacterial cells to be in an unfolded or improperly folded form or in a non-glycosylated form, any recombinant Fab produced in a bacterial cell would have to be screened for retention of antigen binding ability. If the molecule expressed by the bacterial cell was produced in a properly folded form, that bacterial cell would be a desirable host, or in alternative embodiments the molecule may express in the bacterial host and then be subsequently re-folded. For example, various strains of E. coli used for expression are well-known as host cells in the field of biotechnology. Various strains of B. subtilis, Streptomyces, other bacilli and the like may also be employed in this method.

Where desired, strains of yeast cells known to those skilled in the art are also available as host cells, as well as insect cells, e.g. Drosophila and Lepidopteraand viral expression systems. See, e.g. Miller et al., Genetic Engineering, 8:277-298, Plenum Press (1986) and references cited therein.

The general methods by which the vectors may be constructed, the transfection methods required to produce the host cells of the invention, and culture methods necessary to produce the antigen binding protein of the invention from such host cell may all be conventional techniques. Typically, the culture method of the present invention is a serum-free culture method, usually by culturing cells serum-free in suspension. Likewise, once produced, the antigen binding proteins of the invention may be purified from the cell culture contents according to standard procedures of the art, including ammonium sulfate precipitation, affinity columns, column chromatography, gel electrophoresis and the like. Such techniques are within the skill of the art and do not limit this invention. For example, preparation of altered antibodies are described in WO 99/58679 and WO 96/16990.

Yet another method of expression of the antigen binding proteins may utilize expression in a transgenic animal, such as described in U.S. Pat. No. 4,873,316. This relates to an expression system using the animal's casein promoter which when transgenically incorporated into a mammal permits the female to produce the desired recombinant protein in its milk.

In a further aspect of the invention there is provided a method of producing an antibody of the invention which method comprises the step of culturing a host cell transformed or transfected with a vector encoding the light and/or heavy chain of the antibody of the invention and recovering the antibody thereby produced.

In accordance with the present invention there is provided a method of producing an anti-IL-13 antibody of the present invention which binds to and neutralises the activity of human IL-13 which method comprises the steps of;

-   (a) providing a first vector encoding a heavy chain of the antibody; -   (b) providing a second vector encoding a light chain of the     antibody; -   (c) transforming a mammalian host cell (e.g. CHO) with said first     and second vectors; -   (d) culturing the host cell of step (c) under conditions conducive     to the secretion of the antibody from said host cell into said     culture media; -   (e) recovering the secreted antibody of step (d).

Once expressed by the desired method, the antibody is then examined for in vitro activity by use of an appropriate assay. Presently conventional ELISA assay formats are employed to assess qualitative and quantitative binding of the antibody to IL-13. Additionally, other in vitro assays may also be used to verify neutralizing efficacy prior to subsequent human clinical studies performed to evaluate the persistence of the antibody in the body despite the usual clearance mechanisms.

The dose and duration of treatment relates to the relative duration of the molecules of the present invention in the human circulation, and can be adjusted by one of skill in the art depending upon the condition being treated and the general health of the patient. It is envisaged that repeated dosing (e.g. once a week or once every two weeks) over an extended time period (e.g. four to six months) may be required to achieve maximal therapeutic efficacy.

The mode of administration of the therapeutic agent of the invention may be any suitable route which delivers the agent to the host. The antigen binding proteins, and pharmaceutical compositions of the invention are particularly useful for parenteral administration, i.e., subcutaneously (s.c.), intrathecally, intraperitoneally, intramuscularly (i.m.), intravenously (i.v.), or intranasally.

Therapeutic agents of the invention may be prepared as pharmaceutical compositions containing an effective amount of the antigen binding protein of the invention as an active ingredient in a pharmaceutically acceptable carrier. In one embodiment the prophylactic agent of the invention is an aqueous suspension or solution containing the antigen binding proteinin a form ready for injection. In one embodiment the suspension or solution is buffered at physiological pH, In one embodiment the compositions for parenteral administration will comprise a solution of the antigen binding protein of the invention or a cocktail thereof dissolved in a pharmaceutically acceptable carrier. In one embodiment the carrier is an aqueous carrier. A variety of aqueous carriers may be employed, e.g., 0.9% saline, 0.3% glycine, and the like. These solutions may be made sterile and generally free of particulate matter. These solutions may be sterilized by conventional, well known sterilization techniques (e.g., filtration). The compositions may contain pharmaceutically acceptable auxiliary substances as required to approximate physiological conditions such as pH adjusting and buffering agents, etc. The concentration of the antigen binding protein of the invention in such pharmaceutical formulation can vary widely, i.e., from less than about 0.5%, usually at or at least about 1% to as much as about 15 or 20% by weight and will be selected primarily based on fluid volumes, viscosities, etc., according to the particular mode of administration selected.

Thus, a pharmaceutical composition of the invention for intramuscular injection could be prepared to contain about 1 mL sterile buffered water, and between about 1 ng to about 100 mg, e.g. about 50 ng to about 30 mg or about 5 mg to about 25 mg, of an antigen binding protein, for example an antibody of the invention. Similarly, a pharmaceutical composition of the invention for intravenous infusion could be made up to contain about 250 ml of sterile Ringer's solution, and about 1 to about 30 or 5 mg to about 25 mg of an antigen binding protein of the invention per ml of Ringer's solution. Actual methods for preparing parenterally administrable compositions are well known or will be apparent to those skilled in the art and are described in more detail in, for example, Remington's Pharmaceutical Science, 15th ed., Mack Publishing Company, Easton, Pa. For the preparation of intravenously administrable antigen binding protein formulations of the invention see Lasmar U and Parkins D “The formulation of Biopharmaceutical products”, Pharma. Sci. Tech. today, page 129-137, Vol. 3 (3^(rd) April 2000); Wang, W “Instability, stabilisation and formulation of liquid protein pharmaceuticals”, Int. J. Pharm 185 (1999) 129-188; Stability of Protein Pharmaceuticals Part A and B ed Ahern T. J., Manning M. C., New York, N.Y.: Plenum Press (1992); Akers, M. J. “Excipient-Drug interactions in Parenteral Formulations”, J. Pharm Sci 91 (2002) 2283-2300; Imamura, K et al “Effects of types of sugar on stabilization of Protein in the dried state”, J Pharm Sci 92 (2003) 266-274; Izutsu, Kkojima, S. “Excipient crystallinity and its protein-structure-stabilizing effect during freeze-drying”, J. Pharm. Pharmacol, 54 (2002) 1033-1039; Johnson, R, “Mannitol-sucrose mixtures-versatile formulations for protein lyophilization”, J. Pharm. Sci, 91 (2002) 914-922; and Ha, E Wang W, Wang Y. j. “Peroxide formation in polysorbate 80 and protein stability”, J. Pharm Sci, 91, 2252-2264, (2002) the entire contents of which are incorporated herein by reference and to which the reader is specifically referred.

In one embodiment the therapeutic agent of the invention, when in a pharmaceutical preparation, is present in unit dose forms. The appropriate therapeutically effective dose will be determined readily by those of skill in the art. Suitable doses may be calculated for patients according to their weight, for example suitable doses may be in the range of about 0.1 to about 20 mg/kg, for example about 1 to about 20 mg/kg, for example about 10 to about 20 mg/kg or for example about 1 to about 15 mg/kg, for example about 10 to about 15 mg/kg. To effectively treat conditions such as asthma or IPF in a human, suitable doses may be within the range of about 0.1 to about 1000 mg, for example about 0.1 to about 500 mg, for example about 500 mg, for example about 0.1 to about 100 mg, or about 0.1 to about 80 mg, or about 0.1 to about 60 mg, or about 0.1 to about 40 mg, or for example about 1 to about 100 mg, or about 1 to about 50 mg, of an antigen binding protein of this invention, which may be administered parenterally, for example subcutaneously, intravenously or intramuscularly. Such dose may, if necessary, be repeated at appropriate time intervals selected as appropriate by a physician.

The antigen binding proteins described herein can be lyophilized for storage and reconstituted in a suitable carrier prior to use. This technique has been shown to be effective with conventional immunoglobulins and art-known lyophilization and reconstitution techniques can be employed.

In another aspect, the invention provides a pharmaceutical composition comprising an antigen binding protein of the present invention or a functional fragment thereof and a pharmaceutically acceptable carrier for treatment or prophylaxis of atopic diseases/disorders and chronic inflammatory diseases/disorders, for example, asthma, such as allergic asthma, particularly severe asthma (that is asthma that is unresponsive to current treatment, including systemically administered corticosteroids; see Busse W W et al, J. Allergy Clin. Immunol 2000, 106: 1033-1042), “difficult” asthma (defined as the asthmatic phenotype characterised by failure to achieve control despite maximally recommended doses of prescribed inhaled steroids, see Barnes P J (1998), Eur Respir J 12:1208-1218), “brittle” asthma (defines a subgroup of patients with severe, unstable asthma who maintain a wide peak expiratory flow (PEF) variability despite high doses of inhaled steroids, see Ayres J G et al (1998) Thorax 58:315-321), nocturnal asthma, premenstrual asthma, steroid resistant asthma (see Woodcock A J (1993) Eur Respir J 6:743-747), steroid dependent asthma (defined as asthma that can be controlled only with high doses of oral steroids), aspirin induced asthma, adult-onset asthma, paediatric asthma. Antibodies of the invention may be used to prevent, reduce the frequency of, or mitigate the effects of acute, asthmatic episodes (status asthmaticus). Antibodies of the invention may also be used to reduce the dosing required (either in terms of amount administered or frequency of dosing) of other medicaments used in the treatment of asthma. For example, antibodies of the invention may be used to reduce the dosing required for steroid treatment of asthma such as corticosteroid treatment (“steroid sparing”). Other diseases or disorders that may be treated with antibodies of the invention include atopic dermatitis, allergic rhinitis, Crohn's disease, chronic obstructive pulmonary disease (COPD), eosinophilic esophagitis, fibrotic diseases or disorders such as idiopathic pulmonary fibrosis, progressive systemic sclerosis (scleroderma), hepatic fibrosis, hepatic granulomas, schistosomiasis, leishmaniasis, and diseases of cell cycle regulation, e.g. Hodgkins disease, B cell chronic lymphocytic leukaemia. In one embodiment the disorder is severe asthma. In a further embodiment the disorder is a fibrotic disorder such as IPF.

In a yet further aspect, the invention provides a pharmaceutical composition comprising an antigen binding protein of the present invention and a pharmaceutically acceptable carrier for treating atopic diseases/disorders and chronic inflammatory diseases/disorders, for example, asthma, such as allergic asthma, particularly severe asthma (that is asthma that is unresponsive to current treatment, including systemically administered corticosteroids; see Busse W W et al, J. Allergy Clin. Immunol 2000, 106: 1033-1042), “difficult” asthma (defined as the asthmatic phenotype characterised by failure to achieve control despite maximally recommended doses of prescribed inhaled steroids, see Barnes P J (1998), Eur Respir J 12:1208-1218), “brittle” asthma (defines a subgroup of patients with severe, unstable asthma who maintain a wide peak expiratory flow (PEF) variability despite high doses of inhaled steroids, see Ayres J G et al (1998) Thorax 58:315-321), nocturnal asthma, premenstrual asthma, steroid resistant asthma (see Woodcock A J (1993) Eur Respir J 6:743-747), steroid dependent asthma (defined as asthma that can be controlled only with high doses of oral steroids), aspirin induced asthma, adult-onset asthma, paediatric asthma. Antibodies of the invention may be used to prevent, reduce the frequency of, or mitigate the effects of acute, asthmatic episodes (status asthmaticus). Antibodies of the invention may also be used to reduce the dosing required (either in terms of amount administered or frequency of dosing) of other medicaments used in the treatment of asthma. For example, antibodies of the invention may be used to reduce the dosing required for steroid treatment of asthma such as corticosteroid treatment (“steroid sparing”). Other diseases or disorders that may be treated with antibodies of the invention include atopic dermatitis, allergic rhinitis, Crohn's disease, chronic obstructive pulmonary disease (COPD), eosinophilic esophagitis, fibrotic diseases or disorders such as idiopathic pulmonary fibrosis, progressive systemic sclerosis (scleroderma), hepatic fibrosis, hepatic granulomas, schistosomiasis, leishmaniasis, and diseases of cell cycle regulation, e.g. Hodgkins disease, B cell chronic lymphocytic leukaemia. In one embodiment the disorder is severe asthma. In a further embodiment the disorder is a fibrotic disorder such as IPF.

It will be understood that the sequences described herein (SEQ ID NO: 26 to SEQ ID NO: 55 and SEQ NO:62 to SEQ ID NO: 146) include sequences which are substantially identical, for example sequences which are at least 90% identical, for example which are at least 91%, or at least 92%, or at least 93%, or at least 94% or at least 95%, or at least 96%, or at least 97% or at least 98%, or at least 99% identical to the sequences described herein.

For nucleic acids, the term “substantial identity” indicates that two nucleic acids, or designated sequences thereof, when optimally aligned and compared, are identical, with appropriate nucleotide insertions or deletions, in at least about 80% of the nucleotides, at least about 90% to about 95%, or at least about 98% to about 99.5% of the nucleotides. Alternatively, substantial identity exists when the segments will hybridize under selective hybridization conditions, to the complement of the strand.

For nucleotide and amino acid sequences, the term “identical” indicates the degree of identity between two nucleic acid or amino acid sequences when optimally aligned and compared with appropriate insertions or deletions. Alternatively, substantial identity exists when the DNA segments will hybridize under selective hybridization conditions, to the complement of the strand.

The percent identity between two sequences is a function of the number of identical positions shared by the sequences (i.e., % identity=# of identical positions/total # of positions times 100), taking into account the number of gaps, and the length of each gap, which need to be introduced for optimal alignment of the two sequences. The comparison of sequences and determination of percent identity between two sequences can be accomplished using a mathematical algorithm, as described in the non-limiting examples below.

The percent identity between two nucleotide sequences can be determined using the GAP program in the GCG software package, using a NWSgapdna.CMP matrix and a gap weight of 40, 50, 60, 70, or 80 and a length weight of 1, 2, 3, 4, 5, or 6. The percent identity between two nucleotide or amino acid sequences can also be determined using the algorithm of E. Meyers and W. Miller (Comput. Appl. Biosci., 4:11-17 (1988)) which has been incorporated into the ALIGN program (version 2.0), using a PAM120 weight residue table, a gap length penalty of 12 and a gap penalty of 4. In addition, the percent identity between two amino acid sequences can be determined using the Needleman and Wunsch (J. Mol. Biol. 48:444-453 (1970)) algorithm which has been incorporated into the GAP program in the GCG software package, using either a Blossum 62 matrix or a PAM250 matrix, and a gap weight of 16, 14, 12, 10, 8, 6, or 4 and a length weight of 1, 2, 3, 4, 5, or 6.

By way of example, a polynucleotide sequence of the present invention may be identical to the reference sequence of SEQ ID NO: 25, that is be 100% identical, or it may include up to a certain integer number of nucleotide alterations as compared to the reference sequence. Such alterations are selected from the group consisting of at least one nucleotide deletion, substitution, including transition and transversion, or insertion, and wherein said alterations may occur at the 5′ or 3′ terminal positions of the reference nucleotide sequence or anywhere between those terminal positions, interspersed either individually among the nucleotides in the reference sequence or in one or more contiguous groups within the reference sequence. The number of nucleotide alterations is determined by multiplying the total number of nucleotides in SEQ ID NO: 25 by the numerical percent of the respective percent identity (divided by 100) and subtracting that product from said total number of nucleotides in SEQ ID NO: 23, or:

nn≦xn−(xn·y),

wherein nn is the number of nucleotide alterations, xn is the total number of nucleotides in SEQ ID NO: 25, and y is 0.50 for 50%, 0.60 for 60%, 0.70 for 70%, 0.80 for 80%, 0.85 for 85%, 0.90 for 90%, 0.95 for 95%, 0.97 for 97% or 1.00 for 100%, and wherein any non-integer product of xn and y is rounded down to the nearest integer prior to subtracting it from xn. Alterations of the polynucleotide sequence of SEQ ID NO: 25 may create nonsense, missense or frameshift mutations in this coding sequence and thereby alter the polypeptide encoded by the polynucleotide following such alterations.

Similarly, in another example, a polypeptide sequence of the present invention may be identical to the reference sequence encoded by SEQ ID NO: 24, that is be 100% identical, or it may include up to a certain integer number of amino acid alterations as compared to the reference sequence such that the % identity is less than 100%. Such alterations are selected from the group consisting of at least one amino acid deletion, substitution, including conservative and non-conservative substitution, or insertion, and wherein said alterations may occur at the amino- or carboxy-terminal positions of the reference polypeptide sequence or anywhere between those terminal positions, interspersed either individually among the amino acids in the reference sequence or in one or more contiguous groups within the reference sequence. The number of amino acid alterations for a given % identity is determined by multiplying the total number of amino acids in the polypeptide sequence encoded by SEQ ID NO: 24 by the numerical percent of the respective percent identity (divided by 100) and then subtracting that product from said total number of amino acids in the polypeptide sequence encoded by SEQ ID NO: 24, or:

na≦xa−(xa·y),

wherein na is the number of amino acid alterations, xa is the total number of amino acids in the polypeptide sequence encoded by SEQ ID NO: 24, and y is, for instance 0.70 for 70%, 0.80 for 80%, 0.85 for 85% etc., and wherein any non-integer product of xa and y is rounded down to the nearest integer prior to subtracting it from xa.

The following examples illustrate but do not limit the invention.

EXAMPLES Example 1 Construction of recombinant anti-IL-13 antibodies

Original murine mAbs were produced by immunisation of mice with recombinant human IL-13. Spleens from responder animals were harvested and fused to myeloma cells to generate hybridomas. The hybridoma supernatant material was screened for binding. Hybridomas of interest were monocloned using standard techniques. The resulting murine antibody (6A1) comprises the variable regions shown in SEQ ID NO:58 and SEQ ID NO:59. Further details of this murine antibody and a humanised version of this antibody A1L1 (SEQ ID NO: 22 and 24) are described in WO2006/003407 which is herein incorporated by reference. The anti-IL-13 mAb antibody A1L1 was used in several of the following examples as a comparator antibody.

A number of variants of the humanised antibody comprising the heavy chain set out in SEQ ID NO: 22 were produced. These all differed in the CDRH3 region of the antibody (SEQ ID NO: 3).

The base DNA expression constructs for the antibodies of the present invention, SEQ ID NO: 23 (heavy chain) and SEQ ID NO:25 (light chain) were prepared de novo by build-up of overlapping oligonucleotides including restriction sites for cloning into Rld and Rln mammalian expression vectors as well as a human signal sequence. Hind III and Spe I restriction sites were introduced to frame the V_(H) domain containing the signal sequence (SEQ ID NO:56) for cloning into Rld containing the human γ1 constant region. Hind III and BsiWI restriction sites were introduced to frame the V_(H) domain containing the signal sequence (SEQ ID NO: 56) for cloning into Rln containing the human kappa constant region. Alternative constructs were produced using pTT vectors which also included human constant regions. Where appropriate, site-directed mutagenesis (SDM) was used to generate different humanised constructs.

Example 2 Antibody Expression in HEK 293 6E Cells

pTT plasmids encoding the heavy and light chains respectively were transiently co-transfected into HEK 293 6E cells and expressed at small scale to produce antibody. Antibodies were assessed directly from the tissue culture supernatant. Other antibodies were purified using immobilised Protein A columns and quantified by reading absorbance at 280 nm and where indicated, the purified antibody material was assessed in the assays described in the examples set out below.

Where we refer to the antibodies by code (i.e. A1Y100BTrpL1) we are referring to the mAb generated by co-transfection and expression of the noted first and second plasmid, for example ‘A1Y100BTrpL1’ relates to a mAb generated by co-transfection of a plasmid containing the A1Y100BTrp sequence and a plasmid containing the L1 sequence in a suitable cell line.

Example 3 Biacore Analysis of Anti IL-13 Humanised mAbs Kinetic Analysis

The initial screen of CDRH3 mutants was carried out on the ProteOn XPR36 (Biorad). The method was as follows, antihuman IgG (Biacore BR-1008-39) was immobilised on a GLM chip by primary amine coupling, CDRH3 mutant antibodies were then captured on this surface and IL13 passed over at 256, 64, 16, 4, 1 nM with a OnM injection (i.e. buffer alone) used to double reference. 3M MgCl₂ was used to regenerate the capture surface, removing the bound CDRH3 mutant antibodies ready for another cycle of capture and analyte injection. The data was fitted to the 1:1 model using the software inherent to the machine. All work was carried out using antibodies directly from tissue culture supernatants except for the parental antibody which was purified material.

The screen identified several antibodies that appeared to have better kinetic profile than the parental molecule, these same samples were then analysed on the Biacore T100 to confirm the results, using a similar method, in that the same antihuman IgG capture antibody was immobilised on a CM5 chip by primary amine coupling, IL13 was passed over the surface at 256, 64, 16, 4, 1 and 0.25 nM with a OnM used for double referencing, regeneration was with 3M MgCl₂ and the data was fitted to the 1:1 model inherent to the T100. Table 1 details the overall affinities (equilibrium dissociation constant K_(D)) for the selected constructs from the ProteOn screen and the T100 run

TABLE 1 Molecule ProteOn KD (pM) Biacore KD (pM) A1S95TrpL1 Not Analysable 216 A1I96ValL1 395 696 A1Y97PheL1 683 618 A1D98GluL1 873 779 A1H100A AlaL1 Not Analysable 172 A1H100A GluL1 110 195 A1H100A GlnL1 195 278 A1H100A ArgL1 256 307 A1H100A SerL1 131 174 A1H100A ThrL1 158 211 A1H100A ValL1 112 152 A1Y100B AlaL1 75 83 A1Y100B IleL1 75 73 A1Y100B TrpL1 68 95 A1L1 ~450-600* 366 *A1L1 ran several times during the ProteOn screen so range of values obtained

The data highlighted that several mutations at the Y100B residue appeared to improve the overall affinity. In light of this, mutations at this residue that were not present in the initial screen were tested using the ProteOn using the same method as described earlier and again using antibodies direct from tissue culture supernatants. Of the mutations tested A1Y100B VaIL1, appeared to improve the overall affinity (equilibrium dissociation constant K_(D)) with a value of 0.166 nM obtained compared to a parental value of 0.390-0.460 nM. When Y100B Val was tested on the Biacore T100 using the same methodology as described earlier, the equilibrium dissociation constant K_(D) was measured at 0.025 nM compared to a parental value of 0.346 nM.

In light of the work so far being carried out using antibody mutants direct from tissue culture supernatants, purified antibody was produced for A1Y100BL1 mutants Ala, Ile and Trp. These were run on the Biacore T100, using the same method as before and including the A1Y100B VaIL1 mutant which was not purified at this stage. Table 2 shows the data obtained from this experiment.

TABLE 2 Molecule ka (M⁻¹s⁻¹) kd (s⁻¹) KD (nM) A1Y100B ValL1 1.018E+6 3.455E−5 0.034 (supernatant) A1Y100B AlaL1 9.599E+5 3.004E−5 0.031 A1Y100B IleL1 1.149E+6 5.584E−5 0.049 A1Y100B TrpL1 2.572E+6 1.627E−4 0.063 A1L1 1.267E+6 4.560E−4 0.360

The experiment confirmed that the mutants did improve the binding affinity to IL13 compared to the parental molecule.

Given that the purified A1Y100BL1 mutants gave better binding affinities than those obtained from tissue culture supernatants, A1Y100B VaIL1 was purified and run along side the other purified A1Y100BL1 mutants that also improved affinity using the Biacore T100 machine using the method described earlier. Table 3, shows the data obtained from this experiment. This experiment was in good agreement with the data in Table 2 and confirmed the improvement of affinity for the Y100B mutations.

TABLE 3 Molecule ka (M⁻¹s⁻¹) kd (s⁻¹) KD (nM) A1Y100B IleL1 (pur) 9.886E+5 4.214E−5 0.043 A1Y100B ValL1 (pur) 7.757E+5 2.123E−5 0.027 A1Y100B AlaL1 (pur) 8.096E+5 2.583E−5 0.032 A1Y100B TrpL1 (pur) 2.385E+6 1.253E−4 0.053 A1L1(pur) 1.128E+6 3.677E−4 0.326

Example 4 Neutralisation of E. Coli-Expressed Recombinant Human IL-13 in a TF-1 Cell Proliferation Bioassay

TF-1 cells proliferate in response to a number of different cytokines including human IL-13. The proliferative response of these cells for IL-13 can therefore be used to measure the bioactivity of IL-13 and subsequently an assay has been developed to determine the IL-13 neutralisation potency (inhibition of IL-13 bioactivity) of mAbs.

The assay was performed in sterile 96-well tissue culture plates under sterile conditions and all test wells were performed in triplicate. 14 ng/ml recombinant E. Coli-expressed human IL-13 was pre-incubated with various dilutions of mAbs (usually from 93.4 nM titrated in 3-fold dilutions to 0.014 nM) for 1 hour at 37C. An antibody of irrelevant specificity was similarly titrated as a negative control. These samples were then added to 50 μl of TF-1 cells (at a concentration of 2×10⁵ cells per ml) in a sterile 96-well tissue culture plate. Thus the final 1000 assay volume contained various dilutions of mAbs (at a final concentration of 46.7 nM titrated in 3-fold dilutions to 0.007 nM), recombinant E. Coli-expressed human IL-13 (at a final concentration of 7 ng/ml) and TF-1 cells (at a final concentration of 1×10⁵ cells per ml). The assay plate was incubated at 37C for approximately 3 days in a humidified CO₂ incubator. The amount of cell proliferation was then determined using the ‘CellTitre 96® Non-Radioactive Cell Proliferation Assay’ from Promega (catalogue number G4100), as described in the manufacturers instructions. The absorbance of the samples in the 96-well plate was read in a plate reader at 570 nm.

The capacity of the mAbs to neutralise recombinant E. Coli-expressed human IL-13 bioactivity was expressed as that concentration of the mAb required to neutralise the bioactivity of the defined amount of human IL-13 (7 ng/ml) by 50% (═ND₅₀). The lower the concentration of the mAb required, the more potent the neutralisation capacity. The ND₅₀ data provided herein (Table 4) were calculated using Robosage in Microsoft Excel. Graphical representation of the data can be seen in FIG. 1.

TABLE 4 Molecule ND₅₀ (nM) Standard Error (nM) A1L1 9.77 34.82 A1Y100BAla L1 0.92 0.08 A1Y100BIle L1 1.10 0.21 A1Y100BTrpL1 1.25 0.34

Example 5 Construction and Expression of mAb-dAbs Comprising the CDRH3 Variant anti-IL-13 mAb

Using standard molecular biology techniques, genes encoding each of the sequences for the variable heavy regions of the CDRH3 variants of the A1 antibodies were transferred from existing constructs to an expression vector containing the hIgG1 constant region fused to an anti-human IL-4 domain antibody (DOM9-112-210) via a TVAAPS or ASTKGPS linker at the c-terminus of the hlgG1 constant region. Details of the heavy chains constructed are listed in Table 5.

TABLE 5 Molecule Protein DNA number Name Description Seq ID Seq ID BPC1624 A1Y100BAla H- H Chain = A1Y100B Ala H 62 63 TVAAPS-210 L1 chain-TVAAPS linker-DOM9- 112-210 dAb L chain = L1 24 25 BPC1625 A1Y100BIle H- H chain = A1Y100BIle H chain- 64 65 TVAAPS-210 L1 TVAAPS linker-DOM9-112-210 dAb L chain = L1 24 25 BPC1626 A1Y100BTrp H- H chain = A1Y100BTrp H chain- 66 67 TVAAPS-210 L1 TVAAPS linker-DOM9-112-210 dAb L chain = L1 24 25 BPC1627 A1Y100BVal H- H chain = A1Y100BVal H chain- 68 69 TVAAPS-210 L1 TVAAPS linker-DOM9-112-210 dAb L chain = L1 24 25 BPC1628 A1Y100BAla H- H Chain = A1Y100B Ala H 70 71 ASTKGPS-210 L1 chain-ASTKGPS linker-DOM9- 112-210 dAb L chain = L1 24 25 BPC1629 A1 Y100BIle H- H chain = A1Y100BIle H chain- 72 73 ASTKGPS-210 L1 ASTKGPS linker-DOM9-112- 210 dAb L chain = L1 24 25 BPC1630 A1Y100BTrp H- H chain = A1Y100BTrp H chain- 74 75 ASTKGPS-210 L1 ASTKGPS linker-DOM9-112- 210 dAb L chain = L1 24 25 BPC1631 A1Y100BVal H- H chain = A1Y100BVal H chain- 76 77 ASTKGPS-210 L1 ASTKGPS linker-DOM9-112- 210 dAb L chain = L1 24 25

BPC1624, BPC1625, BPC1626 and BPC1627 were expressed in HEK293 cells. Briefly, 250 ml of HEK293 cells at 1.5×10⁶ cells/ml were co-transfected with heavy and light chain expression plasmids previously incubated with 293fectin reagent (Invitrogen # 51-0031). These were placed in a shaking incubator at 37° C., 5% CO₂, and 95% relative humidity. After 24 hours Tryptone feeding media was added and the cells grown for a further 5 days. Supernatant was harvested by centrifugation and filter sterilised. The expressed molecules were purified by affinity chromatography using immobilised Protein A columns and the concentration was determined by measuring the absorbance at 280 nm. The level of aggregated protein in the purified samples was determined by size exclusion chromatography. The yield of purified protein and levels of aggregation are shown in Table 5b.

TABLE 5b BPC Name Yield % aggregate BPC1624 586Y100BA H-TVAAPS-210 0.81 mg 3.6% BPC1625 586Y100BI H-TVAAPS-210 0.944 mg  6.7% BPC1626 586Y100BW H-TVAAPS-210 1.14 mg 5.5% BPC1627 586Y100BV H-TVAAPS-210 1.26 mg 8.4%

Example 6 Neutralisation Activity Data for mAb-dAbs Comprising the CDRH3 Variant Anti-IL-13 mAb

mAb-dAbs comprising the CDRH3 variant anti-IL-13 mAb were tested for neutralisation of E. Coli-expressed recombinant human IL-13 in a TF-1 cell proliferation bioassay

The assay was performed in sterile 96-well tissue culture plates under sterile conditions and all test wells were performed in triplicate. Approximately 20 ng/ml recombinant E. Coli-expressed human IL-13 was pre-incubated with various dilutions of mAbdAbs (usually from 50 nM titrated in 3-fold dilutions to 0.02 nM) (those mAbdAbs made in HEK cells and purified as described in example 5) in a total volume of 500 for 1 hour at 37° C. An antibody of irrelevant specificity was similarly titrated as a negative control (data not shown). These samples were then added to 500 of TF-1 cells (at a concentration of 2×10⁵ cells per ml) in a sterile 96-well tissue culture plate. Thus the final 1000 assay volume contained various dilutions of mAbdAbs (at a final concentration of 25 nM titrated in 3-fold dilutions to 0.01 nM), recombinant E. Coli-expressed human IL-13 (at a final concentration of 10 ng/ml) and TF-1 cells (at a final concentration of 1×10⁵ cells per ml). The assay plate was incubated at 37° C. for approximately 3 days in a humidified CO₂ incubator. The amount of cell proliferation was then determined using the ‘CellTitre 96® Non-Radioactive Cell Proliferation Assay’ from Promega (catalogue number G4100), as described in the manufacturer's instructions. The absorbance of the samples in the 96-well plate was read in a plate reader at 570 nm.

The capacity of the mAbdAbs to neutralise human IL-13 bioactivity was expressed as that concentration of the mAb-dAb required to neutralise the bioactivity of the defined amount of human IL-13 (10 ng/ml) by 50% (═ND₅₀). The lower the concentration of the mAbdAb required, the more potent the neutralisation capacity. The ND₅₀ data provided herein (Table 6) were calculated using Graph Pad Prism. These data are represented graphically in FIG. 2.

TABLE 6 Antibody ID Description ND₅₀ human IL-13 BPC1624 A1Y100BAla H-TVAAPS-210L1 0.553 nM BPC1625 A1Y100BIle H-TVAAPS-210L1 0.542 nM BPC1626 A1Y100BTrp H-TVAAPS-210L1 0.681 nM BPC1627 A1Y100BVal H-TVAAPS-210L1 0.615 nM A1L1 Anti IL-13 antibody 2.524 nM

Example 7 Expression of mAb-dAbs Comprising the CDRH3 Variant Anti-IL-13 mAb in the CHOE1a Expression System

Molecules BPC 1624 to 1631 as shown in Table 5 were also expressed in CHOE1a cells. DNA vectors encoding the heavy and light chains were co-electroporated into suspension CHO cells. Cells were passaged in shake flasks in MR1 basal selective medium at 37° C., 5% CO₂, 130 rpm until cell viability and cell counts improved. CHO cells were then inoculated into MR1 basal x2 selective medium and incubated for 8 to 12 days at 34° C., 5% CO₂, 130 rpm. The cells were pelleted by centrifugation and the supernatant sterile filtered.

Expressed material was purified by affinity chromatography using immobilised protein A columns and the yield determined by measurement of absorbance at 280 nm. The level of aggregates was determined by size exclusion chromatography. Aggregates were removed by preparative size exclusion chromatography and the yield re-assessed. Table 7 lists the yields and levels of aggregate obtained from this expression system.

TABLE 7 Yield (mgs) Aggregates (%) Final Expression (post protein A pre (post protein A pre Final Yield Aggregates Molecule Volume (ml) clean-up) clean-up) (mgs) (%) BPC1628 850 80.70 17.1% 39.50 2.6% BPC1629 850 77.90 20.3% 35.25 2.8% BPC1630 850 69.30 15.7% 38.00 3.3% BPC1631 850 61.47 20.3% 30.00 2.3% BPC1624 850 88.65 15.2% 45.00 2.6% BPC1625 850 77.49 16.2% 37.49 2.3% BPC1626 850 65.16 12.6% 30.80 3.1% BPC1627 850 73.26 15.2% 34.44 1.9%

Example 8 Stoichiometry Assessment of Antigen Binding Proteins (Using Biacore™

This example is prophetic. It provides guidance for carrying out an additional assay in which the antigen binding proteins of the invention can be tested,

Anti-human IgG is immobilised onto a CM5 biosensor chip by primary amine coupling. Antigen binding proteins are captured onto this surface after which a single concentration of IL-13 or IL-4 or IL-5 is passed over, this concentration is enough to saturate the binding surface and the binding signal observed reached full R-max. Stoichiometries are then calculated using the given formula:

Stoich=Rmax*Mw(ligand)/Mw(analyte)*R(ligand immobilised or captured)

Where the stoichiometries are calculated for more than one analyte binding at the same time, the different antigens are passed over sequentially at the saturating antigen concentration and the stoichometries calculated as above. The work can be carried out on the Biacore 3000, at 25° C. using HBS-EP running buffer.

Example 9 Dose Prediction of Improved Humanised Variant mAbs

An antibody-ligand binding PK-PD model was developed in order to rank the different monoclonal antibody (mAb) candidates based on binding affinity and predicted potential therapeutic dose in human.

The predicted potential therapeutic dose in human was defined for this purpose as the dose providing 90% inhibition of the target IL-13 in the lung (site of action) at steady-state following monthly intravenous administration of the mAbs for 1 h. The molecular weight of each molecule was assumed to be the same and equal to the standard molecular weight of a mAb i.e. 150 kDa. In addition, in the absence of animal or human pharmacokinetics data for the different candidates, the human pharmacokinetics of the A1L1 antibody was inferred to all the candidates.

The same antibody-ligand binding PK-PD model is used for each mAb as well as the same assumptions regarding the target concentration, the target turnover, the target tissue:plasma ratio and the mAb tissue penetration. The ranking provided by the model is therefore solely based on the binding affinity of the molecules, the only parameter differing. In such conditions, the potential therapeutic dose in human for the 4 candidates A1Y100BIleL1, A1Y100BValL1, A1Y100BAlaL1 and A1Y100BTrpL1 is predicted to provide a substantial improvement above the predicted potential therapeutic dose in human for A1L1.

Example 10 Anti-IL13/IL4 mAbdAbs with Variant IL-4 dAbs 10.1 Construction and Expression

The anti IL-4 dAb (DOM9-155-154, SEQ ID NO: 80), was investigated for aggregation-prone residues using an aggregation prediction algorithm. The leucine residue, at Kabat position 89 was identified as a key residue for promotion of aggregation.

In order to reduce the aggregation potential of mAbdAbs containing this dAb, this amino acid residue was substituted for other amino acids to generate a number of mAb-dAb variants. Expression constructs were generated by site directed mutagenesis using the DNA expression vector coding for the heavy chain of an existing mAbdAb construct. The protein sequences for the resulting new mAbdAb heavy chains comprising the mutated dAb sequences are given in SEQ ID NOs 117-134.

Other heavy chain sequences incorporating another mutation at position 89 are SEQ ID NOs: 96-106. These are described in detail in Example 11. Table 8 provide a list of the molecules expressed.

TABLE 8 Protein Alternative SEQ ID Identifier names Linker Molecule description NO: BPC1090 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 117 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89G) 155-154 (89G) L chain: Anti-human IL-13 mAb light 24 chain BPC1091 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 118 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89S) 155-154 (89S) L chain: Anti-human IL-13 mAb light 24 chain BPC1092 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 119 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89H) 155-154 (89H) L chain: Anti-human IL-13 mAb light 24 chain BPC1093 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 120 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89M) 155-154 (89M) L chain: Anti-human IL-13 mAb light 24 chain BPC1094 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 121 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89A) 155-154 (89A) L chain: Anti-human IL-13 mAb light 24 chain BPC1095 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 122 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89T) 155-154 (89T) L chain: Anti-human IL-13 mAb light 24 chain BPC1108 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 123 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89C) 155-154 (89C) L chain: Anti-human IL-13 mAb light 24 chain BPC1109 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 124 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89R) 155-154 (89R) L chain: Anti-human IL-13 mAb light 24 chain BPC1110 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 125 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89W) 155-154 (89W) L chain: Anti-human IL-13 mAb light 24 chain BPC1111 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 126 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89E) 155-154 (89E) L chain: Anti-human IL-13 mAb light 24 chain BPC1112 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 127 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89K) 155-154 (89K) L chain: Anti-human IL-13 mAb light 24 chain BPC1113 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 128 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89D) 155-154 (89D) L chain: Anti-human IL-13 mAb light 24 chain BPC1114 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 129 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89N) 155-154 (89N) L chain: Anti-human IL-13 mAb light 24 chain BPC1115 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 130 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89Y) 155-154 (89Y) L chain: Anti-human IL-13 mAb light 24 chain BPC1116 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 131 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89V) 155-154 (89V) L chain: Anti-human IL-13 mAb light 24 chain BPC1117 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 132 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89I) 155-154 (89I) L chain: Anti-human IL-13 mAb light 24 chain BPC1118 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 133 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89F) 155-154 (89F) L chain: Anti-human IL-13 mAb light 24 chain BPC1119 829H- (TVAAPS)₂GS H chain: Anti-human IL-13 mAb heavy 134 (TVAAPS)₂GS-154 chain Y100B_V-(TVAAPS)₂GS-DOM9- (89P) 155-154 (89P) L chain: Anti-human IL-13 mAb light 24 chain

10.2 Molecule Expression in HEK 293 6E Cells

Plasmids encoding the heavy and light chains respectively were transiently co-transfected into HEK 293 6E cells and expressed at small scale to produce antibody molecules. A tryptone feed was added to each cell culture up to 24 hours after transfection and the cells were harvested after 3 days. Antibody molecules were assessed directly from the tissue culture supernatant and quantified using the Gyrolab workstation.

Gyrolab Workstation Method for Quantification of Antibody Molecules in Cell Supernatant

Antibodies produced from small scale transient HEK 2936E transfections (0.75-2.0 ml) were quantified from tissue culture supernatants by a quantitative immunoassay using a Gyrolab Bioaffy Workstation (Gyros). Antibody was captured via the Fc region using a biotinylated anti-IgG Affibody molecule (Abcam) immobilised onto streptavidin-coated particles on a compact disc (CD) microlaboratory (Gyros). The Affibody reagent was vortexed briefly and diluted with PBS-Tween 20 (0.01% v/v) to a final working concentration of 0.1 mg/ml. Antibody was then detected by an ALEXA 647 labelled Fab2 anti-human IgG kappa light chain molecule using laser-induced fluorescence. The ALEXA 647 labelled detection reagent was prepared by vortexing briefly and by centrifugation at 13000 rpm for 4 minutes. The labelled Fab2 detection reagent was added to unlabelled Fab2 which were diluted to final concentrations of 75 nM and 1.5 μM respectively using Rexcip F Detection reagent diluant (Gyros). The antibody quantification range was between 0.244-250 μg/ml relative to an anti-CD23 monoclonal antibody standard curve. The anti-CD23 (1 mg/ml) standard curve was generated by serial dilution of the antibody with tissue culture media (Freestyle 293 Expression Media, Pluronic F68 and Geneticin, Invitrogen).

In some instances, the antibody molecules were purified using immobilised Protein A columns and quantified by reading absorbance at 280 nm and where indicated, the purified antibody molecule was assessed in the assays described in the examples set out below.

10.3 IL-4 Binding ELISA

These mAbdAbs were tested for binding to IL-4 in a direct binding ELISA using the following method.

96-well high binding plates were coated with 5 μg/ml human IL-4 (made at GSK) in NaHCO₃ and stored overnight at 4° C. The plates were washed twice with Tris-Buffered Saline with 0.05% of Tween-20 (TBST). 100 μL of blocking solution (1% BSA in TBST buffer) was added in each well and the plates were incubated for at least one hour at room temperature. The purified mAbdAbs were successively diluted across the plates in blocking solution. After one hour incubation, the plates were washed three times. Goat anti-human kappa light chain specific peroxidase conjugated antibody (Sigma A7164) was diluted in blocking solution to 1 μg/mL and 50 μL was added to each well. The plates were incubated for one hour. After another three washing steps, 50 μl of OPD (o-phenylenediamine dihydrochloride) SigmaFast substrate solution was added to each well and the reaction was stopped after about 5 minutes by addition of 25 μL of 3M sulphuric acid. Absorbance was read at 490 nm using the VersaMax Tunable Microplate Reader (Molecular Devices) using a basic endpoint protocol.

The experiment was carried out using mAbdAbs directly from tissue culture supernatants except for the positive control (anti-IL-4 mAb) and the anti-IL13 negative control mAb, which were purified material. These data are shown in FIG. 17.

The result of the ELISA shows that most of these transiently expressed anti-IL13 mAb-anti-IL4 dAbs bound IL-4, but some variation in IL-4 binding activity was observed. The purified positive control anti-IL-4 mAb, also showed binding to IL-4, whereas the purified negative control mAb showed no binding to human IL-4.

Example 11 Construction and Testing of Antigen Binding Proteins Comprising the CDRH3 Variant anti-IL-13 mAb and a Mutated dAb (BPC1085, BPC1086 & BPC10871 11.1 Construction and Expression

Plasmids encoding heavy chains consisting of an anti-IL-13 mAb and an anti-IL-4 dAb were used as base constructs to generate alternative plasmid constructs. A two step cloning strategy was required. In step 1, the DNA sequence encoding the VH of the anti-IL13 mAb component of the H chain was replaced with the DNA sequence encoding the VH of another humanized anti-IL13 antibody (SEQ ID NO:54) by restriction cloning using HindIII and SpeI. In step 2, the codon encoding the leucine at Kabat position 89 in the anti-IL4 dAb (DOM9-155-154, SEQ ID NO: 80) component of the mAbdAb was mutated by site directed mutagenesis to glutamine. All of the resulting heavy chain DNA sequences generated are given in SEQ ID NOs: 96, 98 and 100. Table 9 provides a list of the molecules constructed and expressed.

TABLE 9 Summary of the antibodies constructed and expressed Alternative Protein Identifier names Linker Molecule description SEQ ID NO: BPC1085 829H- GS(TVAAPSGS)₂ H chain: Anti-human IL- 96 GS(TVAAPSGS)₂- 13 mAb heavy chain 154 (89Q) or Y100B_V- 829H- GS(TVAAPSGS)₂-DOM9- GS(TVAAPSGS)₂- 155-X256 256 L chain: Anti-human IL-13 24 mAb light chain BPC1086 829H- GS(TVAAPSGS)₃ H chain: Anti-human IL- 98 GS(TVAAPSGS)₃- 13 mAb heavy chain 154 (89Q) or Y100B_V- 829H- GS(TVAAPSGS)₃-DOM9- GS(TVAAPSGS)₃- 155-256 256 L chain: Anti-human IL-13 24 mAb light chain BPC1087 829H- GS(TVAAPSGS)₄ H chain: Anti-human IL- 100 GS(TVAAPSGS)₄- 13 mAb heavy chain 154 (89Q) or Y100B_V- 829H- GS(TVAAPSGS)₄-DOM9- GS(TVAAPSGS)₄- 155-256 256 L chain: Anti-human IL-13 24 mAb light chain

Heavy and light chain expression plasmids encoding BPC1085, BPC1086 and BPC1087 mAbdAbs were co-transfected into HEK 2936E cells using 293fectin (Invitrogen, 12347019). A tryptone feed was added to each of the cell cultures after 24 hours and the cells were harvested after 72 hours. The antibodies were purified using a Protein A column before being tested in binding assays.

BPC1085, BPC1086 and BPC1087 mAbdAbs were purified using Protein A affinity. 1 ml Protein A columns were used (GE Healthcare) on the AKTA Xpress system, columns were equilibrated in PBS (Gibco/Invitrogen) and the antibodies eluted using Pierce IgG elute. Eluted fractions were neutralised using 1M Tris (Hydroxymethyl) Aminomethane buffer (in general 5-10% v/v). Eluted antibody fractions were pooled and analysed for aggregation by size exclusion chromatography and quantified by reading at OD₂₈₀ nm using a spectrophotometer.

These were compared to equivalent mAbdAbs (2222, 2223, 2230 and 2231) which are described in Table 10. These comprise:

-   i) a dAb which is identical to that used in BPC1085, BPC1086 and     BPC1087 except for position 89 which is ‘L’ in BPC2222, BPC2223,     BPC2230 & BPC2231 and ‘Q’ in BPC1085, BPC1086 & BPC1087). -   ii) same linkers -   iii) an IL-13 mAb sequence which is identical to that used BPC1085,     BPC1086 and BPC1087 except for position 100B which is ‘Y’ in     BPC2222, BPC2223, BPC2230 & BPC2231 and' V′ in BPC1085,6 & 7).

TABLE 10 Identifier mAb Linker dAb Heavy chain Light chain BPC2222 A1L1 GS(TVAAPSGS)₁ DOM9-155-154 135 24 BPC2223 A1L1 GS(TVAAPSGS)₂ DOM9-155-154 136 24 BPC2230 A1L1 GS(TVAAPSGS)₃ DOM9-155-154 137 24 BPC2231 A1L1 GS(TVAAPSGS)₄ DOM9-155-154 138 24

BPC2222, 2223, 2230 and 2231 mAbdAbs were purified using Protein A affinity. 1 ml Protein A columns were used (GE Healthcare) on the AKTA Xpress system, columns were equilibrated in PBS (Gibco/Invitrogen) and the antibodies eluted using Pierce IgG elute. Eluted fractions were neutralised using 1M Tris (Hydroxymethyl) Aminomethane buffer (in general 5-10% v/v). Eluted antibody fractions were pooled and analysed for aggregation by size exclusion chromatography and quantified by reading at OD₂₈₀ nm using a spectrophotometer.

BPC2222, 2223, 2230 and 2231 showed aggregation of between 30-40%, with the aggregated material eluting before 10 minutes.

Compared to BPC2222, 2223, 2230 and 2231 the constructs BPC1085, 1086 and 1087 showed lower levels of aggregation as assessed by size exclusion chromatography. The SEC profiles for these molecules are shown in FIGS. 3-9

11.2 IL-4 Binding ELISA

Purified BPC1085, BPC1086 and BPC1087 mAbdAbs were tested for binding to IL-4 in a direct binding ELISA according to the method described in Example 10.3.

These data are shown in FIG. 10. The results of the ELISA confirmed that these purified mAbdAbs bound to IL-4. The positive controls anti-IL-4 mAb and BPC2231 also showed binding to IL-4 whereas the negative control mAb (anti IL-13 mAb) showed no binding to IL-4. This indicated in this ELISA the dAb potency increased when the linker length was increased from GS(TVAAPSGS) to GS(TVAAPSGS)₂₋₄.

11.3 Neutralization of IL-4 in a TF-1 Cell Proliferation Bioassay

Purified BPC1085, BPC1086 and BPC1087 mAbdAbs were tested for neutralization of human IL-4 in a TF-1 cell bioassay.

TF-1 cells proliferate in response to a number of different cytokines including human IL-4. The proliferative response of these cells for IL-4 can therefore be used to measure the bioactivity of IL-4 and subsequently an assay has been developed to determine the IL-4 neutralisation potency (inhibition of IL-4 bioactivity) of mAbdAbs.

The assay was performed in sterile 96-well tissue culture plates under sterile conditions and all test wells were performed in duplicate. Approximately 2.2 ng/ml recombinant E. Coli-expressed human IL-4 was pre-incubated with various dilutions of mAbdAbs (usually from 560 nM titrated in 3-fold dilutions to 0.009 nM) in a total volume of 1200 for 1 hour at 37° C. An antibody of irrelevant specificity was similarly titrated as a negative control (anti-IL13 mAb). 500 of these samples were then added to 500 of TF-1 cells (at a concentration of 2×10⁵ cells per ml) in a sterile 96-well tissue culture plate. Thus the final 1000 assay volume contained various dilutions of mAbdAbs (at a final concentration of 270 nM titrated in 3-fold dilutions to 0.005 nM), recombinant E. Coli-expressed human IL-4 (at a final concentration of 1.1 ng/ml) and TF-1 cells (at a final concentration of 1×10⁵ cells per ml). The assay plate was incubated at 37° C. for approximately 4 days in a humidified CO₂ incubator. The amount of cell proliferation was then determined using the ‘CellTitre 96® Non-Radioactive Cell Proliferation Assay’ from Promega (catalogue number G4100), as described in the manufacturers instructions. The absorbance of the samples in the 96-well plate was read in a plate reader at 570 nm. These data were entered on an Excel spreadsheet, values for duplicate test wells were averaged and the average background value (no mAb-dAb and no IL-4 test wells) was subtracted.

The capacity of the mAbdAbs to neutralise recombinant E. Coli-expressed human IL-4 bioactivity was expressed as that concentration of the mAb-dAb required to neutralise the bioactivity of the defined amount of human IL-4 (1.1 ng/ml) by 50% (═ND₅₀). The lower the concentration of the mAbdAb required, the more potent the neutralisation capacity. The ND₅₀ data provided herein (Table 11) were calculated using the Robosage function in Excel. These data are represented graphically in FIG. 11.

An anti-IL-4 mAb and DOM9-155-154 (SEQ ID NO: 80) were included as positive controls for neutralization of human and cynomolgus IL-4 in the TF-1 cell bioassays. Additionally, a dAb with specificity for an irrelevant antigen (dummy dAb) was also included as a negative control for neutralization of human or cynomolgus IL-4 in the TF-1 cell bioassays.

These were repeated several times and FIG. 11 shows the results for one of these experiment s. ND₅₀ values were calculated from the dataset. The ND₅₀ value is the concentration of the mAbdAb or mAb or dAb, which is able to neutralise the bioactivity of IL-4 by 50%.

The mean ND₅₀ value and the number of times tested (n) are shown in table 11.

TABLE 11 Mean ND₅₀ value & Molecule standard deviation (nM) Number of repeats BPC1085 9.21 3 BPC1086 4.32 3 BPC1087 3.59 3 anti-IL-4 mAb 1.95 2 DOM9-155-154 0.98 2 Negative control dAb did not neutralise 2

These data confirm that purified BPC1085, BPC1086 and BPC1087 mAbdAbs, neutralized the bioactivity of human and cyno IL-4. Anti-IL-4 mAb and DOM9-155-154 also neutralised the bioactivity of human and cynomolgus IL-4, whereas the negative dAb (dummy dAb) showed no neutralization in the same bioassay.

All three mAbdAbs show good potency, and there is a clear trend of increasing dAb potency with increasing linker length was apparent from the neutralisation assays, despite the more crude ELISA not picking up this difference in potency. A negative control anti-IL-4 mAb) showed no neutralization in the same bioassay.

11.5 Neutralization of Human IL-13 in a TF-1 Cell Proliferation Bioassay

Purified BPC1085, BPC1086 and BPC1087 mAbdAbs were tested for neutralization of human IL-13 in a TF-1 cell bioassay as described below.

TF-1 cells proliferate in response to a number of different cytokines including human IL-13. The proliferative response of these cells for IL-13 can therefore be used to measure the bioactivity of IL-13 and subsequently an assay has been developed to determine the IL-13 neutralisation potency (inhibition of IL-13 bioactivity) of mAbdAbs. The assay was performed in sterile 96-well tissue culture plates under sterile conditions and all test wells were performed in duplicate. Approximately 14 ng/ml recombinant E. Coli-expressed human IL-13 was pre-incubated with various dilutions of mAbdAbs (usually from 560 nM titrated in 3-fold dilutions to 0.009 nM) in a total volume of 1200 for 1 hour at 37° C. An antibody and dAb of irrelevant specificity was similarly titrated as negative controls (anti-IL-4 mAb and DOM9-155-154 respectively). 500 of these samples were then added to 500 of TF-1 cells (at a concentration of 2×10⁵ cells per ml) in a sterile 96-well tissue culture plate. Thus the final 1000 assay volume contained various dilutions of mAbdAbs (at a final concentration of 270 nM titrated in 3-fold dilutions to 0.005 nM), recombinant E. Coli-expressed human IL-13 (at a final concentration of 7 ng/ml) and TF-1 cells (at a final concentration of 1×10⁵ cells per ml). The assay plate was incubated at 37° C. for approximately 4 days in a humidified CO₂ incubator. The amount of cell proliferation was then determined using the ‘CellTitre 96® Non-Radioactive Cell Proliferation Assay’ from Promega (catalogue number G4100), as described in the manufacturer's instructions. The absorbance of the samples in the 96-well plate was read in a plate reader at 570 nm. These data were entered on an Excel spreadsheet, values for duplicate test wells were averaged and the average background value (no mAb-dAb and no IL-13 test wells) was subtracted.

The capacity of the mAbdAbs to neutralise recombinant E. Coli-expressed human IL-13 bioactivity was expressed as that concentration of the mAb-dAb required to neutralise the bioactivity of the defined amount of human IL-13 (7 ng/ml) by 50% (═ND₅₀). The lower the concentration of the mAbdAb required, the more potent the neutralisation capacity. The ND₅₀ data provided herein (Table 12) were calculated using the Robosage function in Excel. These data are represented graphically in FIG. 12.

An anti IL-13 mAb (SEQ ID NO:22 & 24) was included as a positive control for neutralization of human IL-13 in the TF-1 cell bioassays. Additionally, an anti-IL-4 mAb was also included as a negative control.

FIG. 12 shows the result of the TF-1 cell neutralization assay. ND₅₀ values were calculated from the dataset. The ND₅₀ value is the concentration of the mAbdAb or mAb or dAb, which is able to neutralise the bioactivity of IL-13 by 50%. The mean ND₅₀ value and the number of times tested are shown in Table 12.

TABLE 12 Mean ND₅₀ value & standard Number of Molecule deviation (nM) repeats BPC1085 0.88 1 BPC1086 1.01 1 BPC1087 1.14 1 Anti-IL-13 mAb 5.01 1 anti-IL-4 mAb did not neutralise 1

These data confirm that purified BPC1085, BPC1086 and BPC1087 mAbdAbs, neutralized the bioactivity of recombinant human and cyno IL-13. A negative control anti-IL-4 mAb showed no neutralization in the same bioassay.

Example 12 Re-Humanisation of Anti-IL-13 mAb Light Chain 12.1 Re-Humanisation

The light chain CDRs of the murine antibody 6A1 (The light chain of which is set out in SEQ ID NO:59) were re-grafted onto new frameworks in order to improve the expression of some anti-IL-13 mAb-anti-IL-4 dAb molecules (BPC1085). Codon optimised light chain variable region sequences (summarised in Table 13) were constructed de novo using a PCR-based strategy and overlapping oligonucleotides. PCR primers were designed to incorporate the signal sequence (SEQ ID NO: 56) and to include HindIII and BsiWI restriction sites designed to frame the V_(L) domain and allow cloning into pTT and Rln mammalian expression vectors containing the human kappa C region. Table 13 summarises the re-humanised light chains that have been constructed.

TABLE 13 Light SEQ ID NO: SEQ ID NO: chain Back Nucleotide Amino acid name Description Backbone Mutations sequence sequence P0 Anti-IL-13 808VL IGKV1 39 + N/A 108 109 kappa liqht chain JK2 P1 Anti-IL-13 809VL IGKV1 39 + I2V + Q3L 110 111 kappa light chain JK2 Q0 IGKV3 20 + N/A 112 113 JK2 Q1 IGKV3 20 + I2V, V3L, L4M, 114 115 JK2 E1D, R45K, I58V

12.2 Molecule Expression in HEK 293 6E Cells

Expression properties of the re-humanised light chains were initially examined in mAb format. Plasmids encoding the A1Y100BVAL1 (SEQ ID NO: 54) heavy chain, the existing light chain (SEQ ID NO: 24) and the re-humanised light chains were transiently co-transfected into HEK 293 6E cells using 293fectin (Invitrogen, 12347019). Plasmids were expressed at small scale (2×0.75 ml culture volumes) to produce antibody. A tryptone feed was added to the cell culture after 24 hours and the cells were harvested after a further 72 hours. Table 14 summarises all of the mAbs which were constructed and expressed.

TABLE 14 Protein SEQ Antibody ID Molecule description ID NO: A1Y100BVAL1 H chain: Anti human IL-13 Y100b V mAb 54 L chain: 586 anti-human IL-13 mAb 24 BPC3208 H chain: Anti human IL-13 Y100b V mAb 54 L chain: P0 re-humanised anti-human IL-13 108 mAb BPC3211 H chain: Anti human IL-13 Y100b V mAb 54 L chain: P1 re-humanised anti-human IL-13 110 mAb BPC3219 H chain: Anti human IL-13 Y100b V mAb 54 L chain: Q0 re-humanised anti-human IL-13 112 mAb BPC3220 H chain: Anti human IL-13 Y100b V mAb 54 L chain: Q1 re-humanised anti-human IL-13 114 mAb

Antibody expression was assessed directly from the tissue culture supernatant, by a quantitative immunoassay using a Gyrolab workstation. Antibodies BPC3208 and BPC3211 containing re-humanised light chains (denoted P0 and P1 respectively), exhibited improved expression yields in comparison to the A1Y100BVAL1 mAb. Q0 and Q1 light chains (BPC3219 and BPC3220) did not improve expression of the anti-IL-13 mAb. Expression data is presented in Table 15.

TABLE 15 Antibody ID Total yield in cell supernatant (μg) A1Y100BVAL1 19.9 BPC3208 111.0 BPC3211 115.0 BPC3219 16.0 BPC3220 18.3 12.3 mAb-dAb Expression in HEK 293 6E Cells

As the re-humanised light chains of BPC3208 and BPC3211 exhibited improved expression of the anti-IL-13 mAb, they were examined in the context of an anti-IL-13 mAb-anti IL-4-dAb. Re-humanised light chains P0 and P1 and the 586 (L1) light chain were co-transfected with the 829H-GS(TVAAPSGS)₂-256 heavy chain (SEQ ID NO: 96, details summarised in Table 16) into HEK 293 6E cells using 293fectin (Invitrogen, 12347019). Plasmids were expressed at the 50 to 500 ml scale to produce antibody molecules. A tryptone feed was added to the cell culture after 24 hours and the cells were harvested after a further 48 hours. Antibodies were purified using immobilised Protein A columns and quantified by reading absorbance at 280 nm and where indicated, the purified antibody molecule was assessed in the assays described in the examples set out below. BPC3214 and BPC3215 were analysed by size exclusion chromatography (SEC) as illustrated in FIGS. 13 and 14.

TABLE 16 Protein DNA Antibody Alternative SEQ ID SEQ ID names Linker Molecule description NO: ID NO: BPC1085 829H- GS(TVAAPSGS)₂ H chain: Anti-human IL-13 96 97 GS(TVAAPSGS)₂- mAb heavy chain Y100B V- 256 GS(TVAAPSGS)₂-DOM9- 155-256 L chain: 586 anti-human IL- 24 25 13 mAb light chain BPC3214 808H- GS(TVAAPSGS)₂ H chain: Anti-human IL-13 96 97 GS(TVAAPSGS)₂- mAb heavy chain Y100B V- 256 GS(TVAAPSGS)₂-DOM9- 155-256 L chain: P0 re-humanised 108 109 anti-human IL-13 mAb BPC3215 809H- GS(TVAAPSGS)₂ H chain: Anti-human IL-13 96 97 GS(TVAAPSGS)₂- mAb heavy chain Y100B V- 256 GS(TVAAPSGS)₂-DOM9- 155-256 L chain: P1 re-humanised 110 111 anti-human IL-13 mAb

Consistent with observations in the mAb format, the mAbdAbs containing the re-humanised light chains (BPC3214 and BPC3215) exhibited improved expression in comparison to BPC1085. Representative expression data is summarised in table 17 5.

TABLE 17 Antibody ID Yield of purified mAbdAb (μg/ml) BPC1085 5.6 BPC3214 9.8 BPC3215 7.2

12.4 Human IL-13 Binding ELISA

Purified BPC3214 and BPC3215 were tested for binding to human IL-13 in comparison to BPC1085 (described in Example 10) via a direct binding ELISA. Anti-IL-13 mAb A1Y100BVAL1 and anti-IL-4 mAb were also examined as positive and negative controls respectively. 96-well high binding plates were coated with 500/well of recombinant E. coli-expressed human IL-13 (Batch number: GRITS31061) at 5 μg/ml and incubated at +4° C. overnight. All subsequent steps were carried out at room temperature. The plates were washed 3 times with phosphate-buffered saline with 0.05% of Tween-20. 100 μL of blocking solution (1% BSA in phosphate-buffered saline with 0.05% of Tween-20) was added to each well and the plates were incubated for at least 1 hour at room temperature. Another wash step was then performed. The purified antibodies were successively diluted across the plates in blocking solution. After 1 hour incubation, the plate was washed. Goat anti-human kappa light chain specific peroxidase conjugated antibody was diluted in blocking solution to 0.75 μg/ml and 50 μl was added to each well. The plates were incubated for one hour. After another two wash steps, 50 μl of OPD (o-phenylenediamine dihydrochloride) SigmaFast substrate solution was added to each well and the reaction was stopped by addition of 50 μL of 3M sulphuric acid. Absorbance was read at 490 nm using the VersaMax Microplate Reader (Molecular Devices) using a basic endpoint protocol. These data are shown in FIG. 15. Direct binding ELISA confirmed that BPC3214 and BPC3215 bind to human IL-13. BPC3214 and BPC3215 exhibit similar IL-13 binding potency to BPC1085. Positive control anti-IL-13 mAb A1Y100BVAL1 also showed binding to recombinant IL-13 whereas negative control anti-IL-4 mAb demonstrated no binding to human IL-13.

12.5 Human IL-4 Binding ELISA

Purified BPC3214 and BPC3215 were also tested for binding to recombinant E. coli-expressed human IL-4 in a direct binding ELISA. An ELISA was performed as described in example 4, coating 96-well high binding plates with 500/well of recombinant E. coli-expressed human IL-4 at 5 μg/ml and incubated at +4° C. overnight. These data are shown in FIG. 16. Direct binding ELISA confirms that BPC3214 and BPC3215 bind to human IL-4. BPC1085 was also examined. BPC3214 exhibits similar IL-4 binding potency to BPC1085. Positive control anti-IL-4 mAb also showed binding to recombinant IL-4 whereas negative control anti-IL-13 mAb A1Y100BVAL1 demonstrated no binding to human IL-4.

Example 13 Binding Affinity of mAbdAbs Comprising the Original IL-13 mAb CDRH3 (BPC2222, BPC2223 & BPC2230-2231) for IL-13 and IL-4 as Assessed by BIAcore™ Analysis Method

Protein A was immobilised on a Cl chip by primary amine coupling; this surface was used as a capture surface for the antibody molecules to be tested. Recombinant E. coli-expressed human IL13 was used at 256, 64, 16, 4, and 1 nM, recombinant E. coli-expressed human IL4 was used at 64, 16, 4, 1 and 0.25 nM, with OnM (i.e. buffer alone) used to double reference the binding curves of both IL4 and IL13 binding. Regeneration the Protein A surface was with 100 mM Phosphoric acid. The assay was run at 25° C. using HBS-EP as running buffer. The data was fitted to 1:1 model inherent to the Biacore T100 analysis software.

The results of binding to human IL13 are shown in Table 18 and the result of binding to human IL4 are shown in Table 19.

TABLE 18 Molecule name Molecule description ka (M/s) kd (1/s) KD (nM) BPC2222 586H-GSTVAAPSGS-154 1.31E+06 4.93E−04 0.376 BPC2223 586H-GS(TVAAPSGS)2-154 1.32E+06 4.90E−04 0.372 BPC2230 586H-GS(TVAAPSGS)3-154 1.31E+06 4.88E−04 0.373 BPC2231 586H-GS(TVAAPSSGS)4-154 1.30E+06 5.13E−04 0.394

TABLE 19 Molecule name Molecule description ka (M/s) kd (1/s) KD (nM) BPC2222 586H-TVAAPSGS-154 1.06E+05 1.09E−04 1.027 BPC2223 586H-TVAAPSGSx2- 8.59E+06 1.56E−04 0.018 154 BPC2230* 586H-TVAAPSGSx3- 2.48E+07 2.48E−04 0.010 154 BPC2231* 586H-TVAAPSSGSx4- 4.03E+07 2.31E−04 0.006 154 *The on-rate for BPC2230 and 2231 are beyond the sensitivity of Biacore, but the fact that we cannot accurately analyse this data does indicate that the interaction with IL4 is likely to be of high affinity with a fast on-rate.

Example 14 Binding Affinity of mAbdAbs Comprising the original IL-13 mAb CDRH3 (BPC2222, BPC2231) & Variant Anti-IL-13 mAb CDRH3 (BPC1085-1087) for IL-13 and IL-4 as Assessed by BIAcore™ Analysis Method

Protein A was immobilised on a CM5 chip by primary amine coupling; this surface was used as a capture surface for the antibody molecules to be tested. Recombinant E. coli-expressed human IL13 was used at 256 nM only, Recombinant E. coli-expressed human IL4 was used at 64, 16, 4 and 1 nM, with OnM (i.e. buffer alone) used to double reference the binding curves for both IL4 and IL13 binding. Regeneration the Protein A surface was with 50 mM NaOH. The assay was run at 25° C. using HBS-EP as running buffer. The data was fitted to 1:1 model inherent to the Biacore T100 analysis software.

The results of binding to human IL13 are shown in Table 20, and the results of binding to human IL4 are shown in Table 21.

TABLE 20 Molecule name ka (M/s) kd (1/s) KD (nM) BPC2222 1.64E+05 5.15E−05 0.314 BPC2231 5.36E+08 1.16E−03 0.002 BPC1085 1.87E+07 8.97E−04 0.048 BPC1086 7.99E+07 1.64E−03 0.021 BPC1087 9.86E+07 1.79E−03 0.018

On-rate for BPC1086 and BPC1087 are beyond the sensitivity of Biacore, but the fact that we cannot accurately analyse this data does indicate that the interaction with IL4 is likely to be of high affinity with a fast on-rate.

TABLE 21 Molecule name ka (M/s) kd (1/s) KD (nM) BPC2222 1.44E+06 4.44E−04 0.308 BPC2231 1.56E+06 4.95E−04 0.316 BPC1085 1.20E+06 6.39E−05 0.053 BPC1086 1.28E+06 6.57E−05 0.051 BPC1087 1.13E+06 6.42E−05 0.057

Example 15 Binding Affinity of mAbdAbs Comprising a Number of Variant Anti-IL-13 mAb CDRH3 (BPC1085, BPC1090-BPC1095, & BPC1108-BPC1119) for IL-4 as Assessed by BIAcore™ Analysis Method (Human IL-4 Binding Affinity)

Protein A was immobilised on a CM5 chip by primary amine coupling; this surface was used as a capture surface for the antibody molecules to be tested.

Recombinant E. coli-expressed human IL4 was used at 64, 16, 4, 1 and 0.25 nM. All binding curves were double referenced with a OnM injection (i.e. buffer alone).

Regeneration of the Protein A surface was with 50 mM NaOH. The assay was run at 25° C. using HBS-EP as running buffer. The data was fitted to 1:1 model inherent to the Biacore T100 analysis software.

The results of binding to human IL4 are shown in Table 22.

TABLE 22 Molecule name ka (M/s) kd (1/s) KD (nM) BPC1085 1.07E+07 8.34E−04 0.078 BPC1090 4.34E+06 4.16E−04 0.096 BPC1091 6.05E+06 1.02E−03 0.168 BPC1092 2.27E+06 3.89E−03 1.713 BPC1093 3.84E+06 2.11E−04 0.055 BPC1094 1.46E+06 3.04E−03 2.078 BPC1095 6.78E+06 3.18E−02 4.687 BPC1108 4.38E+06 1.23E−03 0.281 BPC1109 1.20E+06 1.77E−01 147.300 BPC1110 1.07E+06 1.73E−03 1.626 BPC1111 2.98E+06 1.11E−04 0.037 BPC1112* 1.14E+08 3.31E+00 28.980 BPC1113 no binding seen BPC1114 3.89E+06 2.55E−03 0.656 BPC1115** 1.44E+08 3.29E−01 2.292 BPC1116 6.82E+06 2.74E−03 0.402 BPC1117 3.95E+06 9.13E−04 0.231 BPC1118 6.39E+06 2.58E−03 0.405 BPC1119 no binding seen *BPC1112 data has a positive off-rate as a result of the machine being unable to calculate real off-rate, possibly due to the fact it is so rapid, in addition the on-rate for this construct is beyond what is measurable by Biacore, but construct is a very poor binder to IL4. **BPC1115 also has an impossible on-rate, it is outside scope of BIAcore to calculate affinity.

Example 16 IL-13 Binding Affinity of mAbdAbs Comprising the Re-Humanised Light Chain (BPC3214 & BPC3215) Compared to the Original Light Chain (BPC1085) as Assessed by BIAcore™ Analysis Method (Human and Cyno IL-13 Binding Affinity)

Protein A was immobilised on a CM5 chip by primary amine coupling; this surface was used as a capture surface for the antibody molecules to be tested.

Recombinant E. coli-expressed human IL13 and cyno IL13 were used 64, 16, 4, 1 and 0.25 nM. All binding curves were double referenced with a OnM injection (i.e. buffer alone).

Regeneration of the Protein A surface was with 50 mM NaOH. The assay was run at 25° C. using HBS-EP as running buffer. The data was fitted to 1:1 model inherent to the Biacore T100 analysis software.

The results of binding to human and cyno IL13 are shown in Table 23.

TABLE 23 Molecule name ka(M/s) kd (1/s) KD (nM) Comment Binding to human IL13 BPC3214 7.749E+05 7.18E−05 0.093 BPC3215 8.220E+05 5.23E−05 0.064 BPC1085 8.652E+05 6.34E−05 0.073 Binding to cyno IL13 BPC3214* 3.214E+05 5.07E−06 0.015770 Impossible off-rates BPC3215* 3.283E+05 3.13E−06 0.009546 Impossible off-rates BPC1085* 3.552E+05 5.19E−10 0.000001 Impossible off-rates *The off-rates (ka) for cyno IL13 binding to BPC3214, BPC3215 and BPC1085 are beyond the sensitivity of the Biacore T100, this indicates the dissociation rate is very slow and that the interaction is likely to be of very high affinity.

Example 17 Stressor Studies of mAbdAbs With and Without the Mutated dAb

A number of mAbdAbs were placed in PBS or 50 mM acetate buffer and incubated at 37° C. for up to 14 days. They were then analysed for presence of a visual precipitate, soluble aggregate and adherence to concentration stability.

The results indicate that the mAbdAbs comprising the mutated dAb (BPC2222, 2223, 2230, 2231) behaved similarly to the non-mutated dAb (BPC1085, 1086, 1087) both catagories of mAbdAb appeared to be stable in both PBS and acetate buffers over the two week incubation period at 37° C., as indicated by no change in the protein concentration in the solutions. In addition no or very little change was noted for the levels of aggregates in the solutions and no precipitation was observed.

Example 18 PK Assessment

The pharmacokinetics of BPC1085, BPC1086, and BPC1087 were investigated in separate studies following IV administration to rats. The PK of BPC1085 was also investigated in cynomologus monkeys following IV administration.

The PK of all three molecules in rat and BPC1085 in monkey were found to be consistent with that of a standard mAb.

BRIEF DESCRIPTION OF FIGURES

FIG. 1: A graph showing the capacity of the mAbdAbs comprising the Y100B variants to neutralise human IL-13 in a TF-1 cell proliferation assay

FIG. 2: A graph showing the capacity of the mAbdAbs comprising the Y100B variants to neutralise human IL-13 in a TF-1 cell proliferation assay

FIG. 3: SEC trace of BPC2222

FIG. 4: SEC trace of BPC2223

FIG. 5: SEC trace of BPC2230

FIG. 6: SEC trace of BPC2231

FIG. 7: SEC trace of BPC1085

FIG. 8: SEC trace of BPC1086

FIG. 9: SEC trace of BPC1087

FIG. 10: A graph showing binding of purified mAbdAbs (BPC1085, BPC1086 and BPC1087) to human IL-4 as determined by ELISA. The IL-4 control mAb is labelled as ‘pascolizumab’.

FIG. 11: A graph showing neutralization of human IL-4 by purified mAbdAbs (BPC1085, BPC1086 and BPC1087) to human IL-4 in the TF-1 cell bioassay. The IL-4 control mAb is labelled as ‘pascolizumab’.

FIG. 12: A graph showing neutralization of human IL-13 by purified mAbdAbs (BPC1085, BPC1086 and BPC1087) to human IL-13 in the TF-1 cell bioassay. The IL-4 control mAb is labelled as ‘pascolizumab’.

FIG. 13: SEC profile for BPC3214.

FIG. 14: SEC profile for BPC3215.

FIG. 15: A graph showing binding of purified mAbdAbs BPC3214, BPC3215, BPC1085 and control mAbs A1Y100BVAL1 and anti-IL-4 mAb to human IL-13 as determined by ELISA. The IL-4 control mAb is labelled as ‘pascolizumab’.

FIG. 16: A graph showing binding of purified mAbdAbs BPC3214, BPC3215, BPC1085 and control mAbs A1Y100BVAL1 and anti-IL-4 mAb to human IL-4 as determined by ELISA. The IL-4 control mAb is labelled as ‘pascolizumab’.

FIG. 17: A graph showing binding of transiently expressed mAbdAbs to recombinant E. coli-expressed human IL-4 as determined by ELISA. The IL-4 control mAb is labelled as ‘pascolizumab’.

TABLE 24 Sequence Summary Sequence identifier (SEQ ID NO) amino acid Polynucleotide Description sequence sequence Anti IL13 A1, CDRH1 1 — Anti IL13 A1, CDRH2 2 — Anti IL13 A1, CDRH3 3 — CDRH3 alternative 4 — CDRH3 alternative 5 — CDRH3 alternative 6 — CDRH3 alternative 7 — CDRH3 alternative 8 — CDRH3 alternative 9 — CDRH3 alternative 10 — CDRH3 alternative 11 — CDRH3 alternative 12 — CDRH3 alternative 13 — CDRH3 alternative 14 — CDRH3 alternative 15 — CDRH3 alternative 16 — CDRH3 alternative 17 — CDRH3 alternative 18 — Anti IL13 L1, CDRL1 19 — Anti IL13 L1, CDRL2 20 — Anti IL13 L1, CDRL3 21 — Anti IL13 A1 (Heavy Chain) 22 23 Anti IL13 L1 (Light Chain) 24 25 Anti IL13 humanised variant A1 S95 Trp (Heavy 26 27 Chain) Anti IL13 humanised variant A1 196 Val (Heavy 28 29 Chain) Anti IL13 humanised variant A1 Y97 Phe (Heavy 30 31 Chain) Anti IL13 humanised variant A1 D98 Glu (Heavy 32 33 Chain) Anti IL13 humanised variant A1 H100A Ala (Heavy 34 35 Chain) Anti IL13 humanised variant A1 H100A Glu (Heavy 36 37 Chain) Anti IL13 humanised variant A1 H100A Gln (Heavy 38 39 Chain) Anti IL13 humanised variant A1 H100A Arg (Heavy 40 41 Chain) Anti IL13 humanised variant A1 H100A Ser (Heavy 42 43 Chain) Anti IL13 humanised variant A1 H100A Thr (Heavy 44 45 Chain) Anti IL13 humanised variant A1 H100A Val (Heavy 46 47 Chain) Anti IL13 humanised variant A1 Y100B Ala (Heavy 48 49 Chain) Anti IL13 humanised variant A1 Y100B Ile (Heavy 50 51 Chain) Anti IL13 humanised variant A1 Y100B Trp (Heavy 52 53 Chain) Anti IL13 humanised variant A1 Y100B Val (Heavy 54 55 Chain) Signal sequence 56 — Human IL13 57 — Murine 6A1 VH 58 — Murine 6A1 VL 59 — Alternative CDRH1 (Chothia and Kabat numbering) 60 — Alternative CDRH1 (Chothia and Kabat numbering) 61 — A1Y100BAla H-TVAAPS-210 (Heavy chain) 62 63 A1 Y100BIle H-TVAAPS-210 (Heavy chain) 64 65 A1Y100BTrp H-TVAAPS-210 (Heavy chain) 66 67 A1Y100BVal H-TVAAPS-210 (Heavy chain) 68 69 A1Y100BAla H-ASTKGPS-210 (Heavy chain) 70 71 A1 Y100BIle H-ASTKGPS-210 (Heavy chain) 72 73 A1Y100BTrp H-ASTKGPS-210 (Heavy chain) 74 75 A1Y100BVal H-ASTKGPS-210 (Heavy chain) 76 77 DOM9-155-25 78 DOM9-155-147 79 DOM9-155-154 80 DOM9-112-210 81 Linker 82 Linker 83 Linker 84 Linker 85 Linker 86 Linker 87 147-TVAAPS-586 Y100B V Heavy chain 88 147-ASTKG-586 Y100B V Heavy chain 89 154-TVAAPS-586 Y100B V Heavy chain 90 154-ASTKG-586 Y100B V Heavy chain 91 Linker 92 Linker 93 DOM9-155-154 L89Q (aka DOM9-155-256) 94 95 829H-GS(TVAAPSGS)₂-154 L89Q 96 97 829H-GS(TVAAPSGS)₃-154 L89Q 98 99 829H-GS(TVAAPSGS)₄-154 L89Q 100 101 829H-(TVAAPS)₂GS-154 L89Q 102 103 829H-(TVAAPS)₃GS-154 L89Q 104 105 829H-(TVAAPS)₄GS-154 L89Q 106 107 P0 108 109 P1 110 111 Q0 112 113 Q1 114 115 586H-TVAAPS-154 (H chain) 116 Anti-human IL-13 mAb heavy chain Y100B_V- 117 (TVAAPS)₂GS-DOM9-155-154 (89G) Anti-human IL-13 mAb heavy chain Y100B_V- 118 (TVAAPS)₂GS-DOM9-155-154 (89S) Anti-human IL-13 mAb heavy chain Y100B_V- 119 (TVAAPS)₂GS-DOM9-155-154 (89H) Anti-human IL-13 mAb heavy chain Y100B_V- 120 (TVAAPS)₂GS-DOM9-155-154 (89M) Anti-human IL-13 mAb heavy chain Y100B_V- 121 (TVAAPS)₂GS-DOM9-155-154 (89A) Anti-human IL-13 mAb heavy chain Y100B_V- 122 (TVAAPS)₂GS-DOM9-155-154 (89T) Anti-human IL-13 mAb heavy chain Y100B_V- 123 (TVAAPS)₂GS-DOM9-155-154 (89C) Anti-human IL-13 mAb heavy chain Y100B_V- 124 (TVAAPS)₂GS-DOM9-155-154 (89R) Anti-human IL-13 mAb heavy chain Y100B_V- 125 (TVAAPS)₂GS-DOM9-155-154 (89W) Anti-human IL-13 mAb heavy chain Y100B_V- 126 (TVAAPS)₂GS-DOM9-155-154 (89E) Anti-human IL-13 mAb heavy chain Y100B_V- 127 (TVAAPS)₂GS-DOM9-155-154 (89K) Anti-human IL-13 mAb heavy chain Y100B_V- 128 (TVAAPS)₂GS-DOM9-155-154 (89D) Anti-human IL-13 mAb heavy chain Y100B_V- 129 (TVAAPS)₂GS-DOM9-155-154 (89N) Anti-human IL-13 mAb heavy chain Y100B_V- 130 (TVAAPS)₂GS-DOM9-155-154 (89Y) Anti-human IL-13 mAb heavy chain Y100B_V- 131 (TVAAPS)₂GS-DOM9-155-154 (89V) Anti-human IL-13 mAb heavy chain Y100B_V- 132 (TVAAPS)₂GS-DOM9-155-154 (89I) Anti-human IL-13 mAb heavy chain Y100B_V- 133 (TVAAPS)₂GS-DOM9-155-154 (89F) Anti-human IL-13 mAb heavy chain Y100B_V- 134 (TVAAPS)₂GS-DOM9-155-154 (89P) Anti-IL-13 mAb heavy chain-GS(TVAAPSGS)₁- 135 — DOM9-155-154 Anti-IL-13 mAb heavy chain-GS(TVAAPSGS)₂- 136 — DOM9-155-154 Anti-IL-13 mAb heavy chain-GS(TVAAPSGS)₃- 137 — DOM9-155-154 Anti-IL-13 mAb heavy chain-GS(TVAAPSGS)₄- 138 DOM9-155-154 GS(TVAAPSGS)₁ 139 GS(TVAAPSGS)₂ 140 GS(TVAAPSGS)₃ 141 GS(TVAAPSGS)₄ 142 GS(TVAAPSGS)₅ 143 GS(TVAAPSGS)₆ 144 (TVAAPS)₂(GS)₁ 145 (TVAAPS)₃(GS)₁ 146 

1. An antigen binding protein which binds human IL-13 and which comprises the CDRH3 SIYDDYHYDDYYAMDY (SEQ ID NO: 3), wherein CDRH3 comprises one or more of the following substitutions: g) S95 in position 1 is substituted for tryptophan (W) h) 196 in position 2 is substituted for valine (V) i) Y97 in position 3 is substituted for phenylalanine (F) j) D98 in position 4 is substituted for glutamine (E) k) H100A in position 7 is substituted for alanine (A), glutamic acid (E), glutamine (Q), Arginine (R), Serine (S), threonine (T) or valine (V), and l) Y100B in position 8 is substituted for alanine (A), isoleucine, (1), tryptophan (W) or valine (V).
 2. The antigen binding protein according to claim 1 wherein CDRH3 is substituted at Y100B in position 8 to an amino acid selected from alanine (A), isoleucine, (I), tryptophan (W) or valine (V).
 3. The antigen binding protein according to claim 1 which binds human IL-13 and which comprises a CDRH3 sequence selected from those set out in SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO:8 and SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13, SEQ ID NO:14 and SEQ ID NO: 15, SEQ ID NO: 16, SEQ ID NO: 17 and SEQ ID NO:
 18. 4. The antigen binding protein according to claim 1 wherein said antigen binding protein further comprises the following CDR sequences: CDRH1: SEQ ID NO:1, CDRH2: SEQ ID NO: 2; CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.
 5. The antigen binding protein according to claim 1 wherein said antigen binding protein comprises the following CDRs: CDRH1: SEQ ID NO:1, CDRH2: SEQ ID NO: 2; CDRH3: SEQ ID NO: 18 CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.
 6. The antigen binding protein according to claim 1 wherein said antigen binding protein comprises the following CDRs: CDRH1: SEQ ID NO:1, CDRH2: SEQ ID NO: 2; CDRH3: SEQ ID NO: 17 CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.
 7. The antigen binding protein according to claim 1 wherein said antigen binding protein comprises the following CDRs: CDRH1: SEQ ID NO:1, CDRH2: SEQ ID NO: 2; CDRH3: SEQ ID NO:16 CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.
 8. The antigen binding protein according to claim 1 wherein said antigen binding protein comprises the following CDRs: CDRH1: SEQ ID NO:1, CDRH2: SEQ ID NO: 2; CDRH3: SEQ ID NO:15 CDRL1: SEQ ID NO:19; CDRL2: SEQ ID NO:20; and CDRL3: SEQ ID NO:21.
 9. The antigen binding protein according to claim 1 wherein the antigen binding protein comprises an antibody.
 10. The antibody according to claim 9 wherein the antibody is a humanised antibody.
 11. The antigen binding protein of claim 10 wherein the antibody is of IgG isotype.
 12. The antigen binding protein according to claim 1 comprising a heavy chain selected from SEQ ID NO: 26, SEQ ID NO: 28, SEQ ID NO: 30, SEQ ID NO: 32, SEQ ID NO: 34, SEQ ID NO: 36, SEQ ID NO: 38, SEQ ID NO: 40, SEQ ID NO: 42, SEQ ID NO: 44, SEQ ID NO: 46, SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52 and SEQ ID NO: 54; and the light chain of SEQ ID NO: 24, 108, 110, 112 and
 114. 13. The antigen binding protein according to claim 13 comprising a heavy chain selected from SEQ ID NO: 48, SEQ ID NO: 50, SEQ ID NO: 52 and SEQ ID NO: 54; and the light chain of SEQ ID NO:108 and
 110. 14. The antigen binding protein according to claim 13 comprising the heavy chain of SEQ ID NO: 54 and the light chain of SEQ ID NO:108.
 15. The antigen binding protein according to claim 13 comprising the heavy chain of SEQ ID NO: 54 and the light chain of SEQ ID NO:110.
 16. The antibody according to claim 10 comprising a mutated Fc region such that said antibody has reduced ADCC and/or complement activation.
 17. The antigen binding protein according to claim 1 which is capable of binding to IL-13 and which is also capable of binding to at least one of IL-4 and IL-5.
 18. The antigen binding protein according to claim 17 which comprises at least one dAb selected from SEQ ID NO: 78, 79, 80, 81 and
 94. 19. The antigen binding protein according to claim 18 which comprises a heavy chain selected from any one of SEQ ID NO: 62, 64, 66, 68, 70, 72, 74, 76, 96, 98, 100, 102, 104, 106, and 117-138 and the light of SEQ ID NO: 24, 108, 110, 112 and
 114. 20. The antigen binding protein according to claim 19 which comprises a heavy chain selected from any one of SEQ ID NO: 96, 98, 100, 102, 104, 106 and the light of SEQ ID NO: 24, 108 and
 110. 21. The antigen binding protein according to claim 20 comprising the heavy chain of SEQ ID NO: 96 and the light chain of SEQ ID NO:24, or the SEQ ID NO: 96 and the light chain of SEQ ID NO:108, or the SEQ ID NO: 96 and the light chain of SEQ ID NO:110, or the SEQ ID NO: 98 and the light chain of SEQ ID NO:24, or the SEQ ID NO: 98 and the light chain of SEQ ID NO:108, or the SEQ ID NO: 98 and the light chain of SEQ ID NO:110, or the SEQ ID NO: 100 and the light chain of SEQ ID NO:24, or the SEQ ID NO: 100 and the light chain of SEQ ID NO:108, or the SEQ ID NO: 100 and the light chain of SEQ ID NO:110.
 22. A recombinant transformed or transfected host cell comprising a first and second vector, said first vector comprising a polynucleotide encoding a heavy chain of an antibody according to claim 1 and said second vector comprising a polynucleotide encoding a light chain of claim
 1. 23. A pharmaceutical composition comprising an antigen binding protein of claim 1 and a pharmaceutically acceptable carrier.
 24. A method of treating a human patient with allergic asthma, severe asthma, difficult asthma, brittle asthma, nocturnal asthma, premenstrual asthma, steroid resistant asthma, steroid dependent asthma, aspirin induced asthma, adult-onset asthma, paediatric asthma, atopic dermatitis, allergic rhinitis, Crohn's disease, COPD, fibrotic diseases or disorders such as idiopathic pulmonary fibrosis, progressive systemic sclerosis, hepatic fibrosis, hepatic granulomas, schistosomiasis, leishmaniasis, diseases of cell cycle regulation such as Hodgkins disease, B cell chronic lymphocytic leukaemia which method comprises the step of administering a therapeutically effective amount of an antigen binding protein of claim
 1. 25. Use of an antigen binding protein according to claim 1 in the preparation of a medicament for treatment or prophylaxis of Allergic asthma, severe asthma, difficult asthma, brittle asthma, nocturnal asthma, premenstrual asthma, steroid resistant asthma, steroid dependent asthma, aspirin induced asthma, adult-onset asthma, paediatric asthma, atopic dermatitis, allergic rhinitis, Crohn's disease, COPD, fibrotic diseases or disorders such as idiopathic pulmonary fibrosis, progressive systemic sclerosis, hepatic fibrosis, hepatic granulomas, schistosomiasis, leishmaniasis, diseases of cell cycle regulation such as Hodgkins disease, B cell chronic lymphocytic leukaemia.
 26. The antigen binding protein according to claim 1 for use in the treatment or prophylaxis of Allergic asthma, severe asthma, difficult asthma, brittle asthma, nocturnal asthma, premenstrual asthma, steroid resistant asthma, steroid dependent asthma, aspirin induced asthma, adult-onset asthma, paediatric asthma, atopic dermatitis, allergic rhinitis, Crohn's disease, COPD, fibrotic diseases or disorders such as idiopathic pulmonary fibrosis, progressive systemic sclerosis, hepatic fibrosis, hepatic granulomas, schistosomiasis, leishmaniasis, diseases of cell cycle regulation such as Hodgkins disease, B cell chronic lymphocytic leukaemia.
 27. A method for reducing the aggregation of an immunoglobulin single variable domain comprising the steps of a) measuring the aggregation levels of an immunoglobulin single variable domain b) mutating kabat position 89 to Glutamine; c) measuring the aggregation levels of a the mutated immunoglobulin single variable domain; wherein the binding activity is retained and aggregation levels of the mutated immunoglobulin single variable domain are lower than the aggregation levels of the un-mutated immunoglobulin single variable domain.
 28. A human VK dAb derived from a germline framework selected from IGKV1-17, IGKV1D-17, IGKV1/OR2-108, IGKV1-6, IGKV5-2, IGKV1D-42, IGKV2-24, IGKV2-28, IGKV2-30, IGKV2-40, IGKV2D-29, IGKV2D-30, IGKV2D-24 and IGKV6-21 wherein residue 89 (kabat numbering) of the human VK dAb is Glutamine.
 29. An Immunoglobulin single variable domain comprising the sequence of SEQ ID NO:94. 